Biology and Geology 3 Teacher's Guide sample unit

DEMO

3

SECONDARY EDUCATION

BIOLOGY AND GEOLOGY S. Clem en t e, A. D o m í n guez, A. B. R ui z

T e a c h e r’s G u i d e

Building

Blocks

Building Blocks is an educational project of Anaya Educación for Secondary Education with the participation of: S. Clemente, A. Domínguez, A. B. Ruiz, Danny Latimer, Hannah Peat, Karen Piper, Denise Suárez, Begoña Fuente Larrazabal, Sara Gascón Martin.

The following people have also contributed to this book:

Editorial team: Hannah Peat and the Departamento de Ciencias Naturales (Almudena Alcón, Esther Fernández, M.a Isabel García, Marco Sánchez, Mercedes Sacristán y Jorge Torres).

Design, technical drawings and maps: Patricia G. Serrano, Juan Carlos Quignon, Miguel Á. Castillejo, Miguel Á. DíazRullo y Miriam Arribas

Layout: Oscar Latorre and Nieves Merino Graphic Edition: Olga Sayans Academic and Professional Orientation: created in conjunction with Fundación Bertelsmann. Coordinator: Juan José Juárez Calvo. Expert collaborators: Sara Lozano Santiago, Belén Pérez Castro and Pilar Vázquez Hernández.

Commitment to Sustainable Development Goals Our publications contain carefully selected content, illustrations and language to comply with non-discrimination on the grounds of gender, culture or opinion.

Grupo Anaya considers social and environmental responsibility to be one of its fundamental values. For this reason, we are committed to: · continually improving our contents and materials related to the environment. · reducing our carbon emissions. · using natural resources responsibly. · making sure that our activity has no negative consequences for endangered forests.

These commitments, among others, mean that 100% of the paper used in our books has the PEFC label.

Important: The links to webpages which appear in this book have been checked before printing. The publisher cannot be liable for any changes or modifications which occur after the date of publication.

© GRUPO ANAYA, S.A., 2021 - C/ Juan Ignacio Luca de Tena, 15 - 28027 Madrid.

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior permission of the publishers.

Contents Building Blocks and the project keys ...........................................................................

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Our project .....................................................................................................................................

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8

Units The scientific method ............................................................................................................

1. The organisation of the human body ....................................................... 20 2. Nutrition and food ....................................................................................... 34 3. Systems of the nutrition function ............................................................. 48 4. The interaction function ............................................................................. 64 5. Reproduction ................................................................................................ 82 6. Health and illness ......................................................................................... 96 7. Dynamic earth ............................................................................................... 110 8. Landform modelling .................................................................................... 122

A PROJECT ROOTED IN SKILLS-BASED LEARNING, DEVELOPING STUDENT ENGAGEMENT AND MAXIMISINGPRODUCTIVITY IN THE CLASS

Building Blocks is a new competence-based learning approach, applying the utmost curricular rigour and a coherent and coordinated content sequence in the areas of this educational stage. It promotes linguistic communication skills, which are essential for assessing our knowledge and understanding of the world around us and for developing social awareness.

Building Blocks offers the possibility of incorporating active methodologies, using cooperative learning and thinking strategies, promoting personal and social skills for emotion management and the development of entrepreneurship in a flexible way.

It attends to academic and professional orientation, whilst embracing equality and inclusion, all within the framework of the Sustainable Development Goals that we must keep focused on over the coming years.

project keys SDG

SDG Commitment Establishes the Sustainable Development Goals as a framework for learning that encourages committed citizenship.

Linguistic Plan Develops communication skills both written and spoken and the tools needed to describe, present, instruct, comment, defend or refute ideas.

Developing thinking Proposes

strategies to stimulate reflection, “learning how to think” and the development of critical and creative thinking habits.

Cooperative learning Offers techniques to develop the skills that allow us to work together and efficiently in a diverse society.

Emotional education Offers emotional management tools to face the challenges of this complex educational stage.

Enterprising culture Promotes entrepreneurial thinking with in three dimensions: personal, social and productive.

ICT Integrates the use of ICT in the learning process itself in a responsible, intelligent and ethical way.

Academic and professional orientation Helps

students to get to know themselves, to understand the academic and professional environment and to make decisions that allow them to confidently enter the labour market.

Assessment Incorporates strategies that allow students to participate in the assessment of their learning, analysing “what they have learned” and “how they have learned it”.

Our project The student’s book The books present content and activities that are adjusted to the curricular development of our community. Under a skills-based methodology they allow us to respond, in a creative and innovative way, to our commitment to the Sustainable Development Goals and enable the growth of the skills and aptitudes demanded by our increasingly diverse society.

The digital project for teachers The web www.anayaeducacion.es The teacher’s website is a tool that facilitates and enriches teaching work. With it, you can adapt the contents to the needs of the students through additional resources or reinforce the most relevant educational aspects: •C ourse plan, the teacher’s guide and project documents.

• Diversity and inclusion, to meet the diversity of students’ motivations, interests and learning styles through: - Key concepts and additional worksheets.

- Extension worksheets and competece development worksheets.

- Tasks, workshops and other resources.

•A ssessment, a core value of the project, is supported through: - Predesigned assessment tests and records.

- Specific information.

- Assessment tools.

•R esource bank, with scientific readings, science workshops, educational videos, self-assessments, key concepts, infographics, learn by playing, Language Bank, Create and more.

•L anguage Bank: created to further develop the four linguistic skills (speaking and writing, productive skills, and reading and listening, receptive skills), this new educational tool can be used both by the teacher and the language assistant.

•C reate: fun cross-curricular projects which contribute to integrating and exposing students to different curricular contents and developing their English skills. These projects show the students that what they’re learning isn’t just in the classroom, but found in everyday lives.

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0:40/1:33

teacher’s guide There is a teacher’s guide for each student book with the solutions to the activities, methodological guidelines, suggestions for applying the project keys, etc.

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3

the digital book All Building Blocks books have a digital version. You can download the entire book or download it by units, with all its resources or in its lighter version (without the largest digital resources), which allows offline and online use.

The resources of each unit are grouped by type and allow direct access to the web resource bank and the Teacher’s guide.

and for the s tudents?

Resource bank

at www.a n

ayaeduca cion.es: • Resourc es related to the proje • Feature ct keys. d resourc e materia l.

• Resourc es for ea ch unit.

Digital b ook A digital version o f the textb be down ook that loaded in can full or by its resourc u nits; with es or a lig all h ter versio the heav n (withou iest digit t al resourc es).

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The organisation of the human body

Unit introduction

This unit is an introduction to the human body. It sets out basic content about how the body is organised, which students need to know for subsequent units in which they will study human anatomy and physiology.

Over the course of the unit, we describe the levels of organisation of living matter, we look in detail at the structure of a human cell and its organelles and functions, we provide a brief description of the process of cell differentiation, and we explain the characteristics and function of the different tissues that make up the human body.

To finish the unit, we provide comprehension activities in which students apply what they have learnt, and tasks designed to foster an interest in science and motivate students.

Resources and materials In addition to the Student’s Book and Teacher’s Guide, the resources in the following sections of the teachers’ web are designed to help with this unit: ‘Course plans, Teacher’s Guide and Project Documents’, ‘Assessment’, ‘My Online Resources’ and ‘Diversity and Inclusion’. Remember, this last section gives you access to an extensive collection of printable sheets of various kinds (curriculum adaptation, practice exercises and further study), organised by content, allowing you to cater for all learners.

General suggestions Preconceptions and learning difficulties At the start of the unit, it would be worth identifying any preconceptions among students about the characteristics of human cells and how they are organised and linked to one another. We suggest checking if they are familiar with different kinds of cell and if they associate human beings with animal cells.

It would also be useful for students to reflect on how matter is organised into more and more complex levels. In this unit the cell is covered in more detail than in previous years, particularly in respect of the structure of the nucleus and the functions of certain organelles, with which students will be unfamiliar. It is worth looking closely at the concept of cell differentiation, which they might find difficult to understand.

Related tasks To familiarise students with the scientific method and help them develop skills such as recording data, group work and decision-making based on evidence, and also a sense of wonder and an interest in science, we propose a research project for each term, divided into steps spread out over the units. To tackle the first step, which is covered in this unit, we suggest you plan the tasks required for this step at the start, in particular that you organise the work groups.

Over the course of this unit, it might also be helpful and motivating to do some practical tasks, in order to help students consolidate the steps of the scientific method.

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KC : key co m p e te n ce s , C LC : co m p e te n ce i n l i n g u i st i c communication, CMST: mathematical competence and basic competences in science and technology, DC: digital competence, LL: learning to learn, SCC: social and civic competence, SIE: sense of initiative and entrepreneurship, and CAE: cultural awareness and expression.

CONTENT AND COMPETENCES Unit content

Key competences

Opening pages • Ada Yonath. Curious by nature

CLC, CMST, DC, SCC, CAE

1. Levels of organisation • Atomic level, molecular level, cellular level

CLC, CMST, DC, SCC, LL

2. The human cell • The plasma membrane • The nucleus • The cytoplasm • Cell organelles

CLC, CMST, DC, SCC

3. Cell differentiation • Cell differentiation

CLC, CMST, DC

4. Human tissues • Epithelial tissue • Connective tissue • Muscle tissue • Nervous tissue

CLC, CMST, DC, LL

5. Organs and systems • Organs • Systems • The internal environment

CLC, CMST, DC , SCC

Research project • Invesitgating healthy habits for the heart (step 1)

CLC, CMST, SIE, LL, CAE

Revise and practise • Organising your ideas • Summarising • Interpreting pictures • Applying your knowledge • Moving forward • Sustainable Development Goals: Goal 3.

CLC, CMST, DC, LL, SCC, SIE

ICT The resource ‘What you need to know’, available at anayaeducacion.es, will help students recall the concepts, definitions, etc. that they should know from previous years.

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Project keys

Speaking

The Organisation of the human BODY

2

Discuss with a partner: a) What are the most important qualities for a scientist to have? b) Do you have any of these qualities? c) Are these qualities different from those needed in other subject areas? d) How can these qualities be inspired and encouraged within scientific education? What would you change within science classes?

Ada Yonath. Curious by nature

Linguistic plan

To be a scientist, you must be curious. And believe me, I have always been curious! When I was five years old, I tried to find out the height of our apartment and broke my arm!

My name is Ada Yonath and I was born in Jerusalem, Israel in 1939. My family never had much money, so I had to work a lot to be able to study: I gave private classes, I babysat, I cleaned the chemistry lab... It was hard, but it gave me the opportunity to learn and research in secret, so I can’t complain.

•W riting and speaking (productive skills), listening and reading (receptive skills)

Enterprising culture • Responsibility, community and common good (social dimension) ICT • Presentations, documents and videos: ‘What you need to know’, ‘The composition of living matter’, ‘Prokaryotic and eukaryotic cells’, ‘The size of a cell’, ‘Observing cells’, ‘Transport through the membrane’, ‘Organs and systems of the human body’, ‘Language Bank: speaking’, ‘Language Bank: writing’, ‘The parts add up’, ‘The What If’, ‘The mirror’, ‘A dichotomous key for identifying tissues’, ‘Science workshop: Observing mucosa cells’, ‘Science workshop: Studying how transport occurs through the membrane’, ‘How to draw a chain of sequences’, ‘Sustainable Development Goals. Goal 3’ • Fact files: ‘Key concepts’ • Interactive games: ‘Learn by playing’ • Plus: Interactive activities, videos and presentations for revising and extending content.

Academic and professional orientation • Reflection on the qualities that a scientist should have

We could encourage patience by doing more experiments that last a longer amount of time.

I specialise in a technique that involves creating crystals and observing them using x-rays. The problem was that the ribosome crystals we made broke extremely easily. We spent years destroying crystals until, one day, we found a way to make ribosome crystals strong enough that we could observe their structure in detail.

Writing An interview

This discovery won me the 2009 Nobel Prize in Chemistry, among other awards. While prizes don’t matter much to me, I’m really proud that my discovery can be used to attack the ribosomes of bacteria and develop new antibiotics to keep winning the fight against infections.

3 Similar to Ada Yonath’s discovery of how to manufacture stronger ribosome crystals, there are many other inventions that have helped improve our understanding of the human body. Choose any medical invention or technique and write an imaginary interview with their inventor(s).

1 a) Why won’t Ada complain about having to work so

• Goal 3

Cooperative learning • Puzzles

I think the most important quality of a scientist is to be patient.

Starting my career as a researcher was amazing. I was interested in something that seemed impossible: discovering what ribosomes looked like and how they worked. Ribosomes are responsible for decoding the DNA instructions in cells and using them to build proteins. But what exactly was their structure? We didn’t know.

SDG commitment

Developing thinking • The parts add up • The mirror • The What If • Chain of sequences

For Ada Yonath, curiosity is the most important quality necessary to be a scientist. She says that from a young age she was curious to explain everything she saw around her.

Include: ➜ What problem they were trying to solve ➜ How they developed their invention and how long it took ➜ What it allowed them to discover ➜ How they felt about the process

hard when she was younger? b) What do Ribosomes do? c) Why was it difficult to observe ribosome crystals using x-rays?

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The organisation of the human body Suggested methodology By reading this biography, students will discover one of the most important qualities of a person who wants to work in research: curiosity. As well as being curious, Ada Yonath was perseverant, which allowed her to accomplish her goals. The text will also introduce students to the study of cell organelles.

It might be helpful to read this text using the cooperative learning skill: ‘Shared reading’.

1 a) Ada won’t complain about having to work so hard when she was younger because it gave her an opportunity to learn and research. b) Ribosomes decode the DNA instructions in cells and use them to build proteins. c) It was difficult to observe ribosome crystals using x-rays because they are very fragile so they broke easily.

Speaking 2 a), b), c), d) - open answers. This question aims to get students to think about the qualities and characteristics that are necessary to be a good scientists. It also encourages them to compare these with the qualitites fostered within other subjects, allowing them to think about similarities and differences between different subjects. The worksheet in the Language Bank provides students with vocabulary to talk about different qualities and attributes. It also provides a space for self reflection about what kinds of classes support them in their learning, which could be interesting for the teacher or language assistant to hear.

Writing 3 Students have to write an interview with the inventor of a medical invention or technique. This will give students a chance to do research about an area that interests them. The Language Bank worksheet provides support on how to write an interview in English. If you have a language assistant in the classroom they could provide a good source of inspiration to students by helping them think of different inventions and supporting them with writing an interview. You could also use examples from real interviews to help inspire and motivate students.

Assessment • Revise and practise • Creating a portfolio

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1

Levels of organisation

Unit 1

LEVELS OF ORGANISATION

Like other living beings, human beings are made up of cells that group together to form more complex structures, such as tissues and organs.

Biomolecules make up living beings Carbohydrates Carbohydrates are a cell’s main source of energy. They form part of some cell structures and are used to build other biomolecules.

Levels of organisation are the different degrees of complexity into which living matter is structured.

The elements in each level join together to form other more complex levels. Each new level has new characteristics and properties, making them more complex than just a collection of the elements in the previous level.

They can be complex, like cellulose, which forms the walls of plant cells, or simple, like glucose.

1.1 Atomic level

Lipids

Atoms are the smallest units of matter that have the properties of a chemical element. Hydrogen (H), oxygen (O) and calcium (Ca) are all atoms.

Atoms that form part of living matter are called bioelements.

Lipids are very chemically diverse.

Some, like phospholipids and cholesterol, form part of cell membranes. Others, like triglycerides, provide and store energy for cells.

1.2 Molecular level Proteins

1.3 Cellular level

All human cells are eukaryotic* animal cells, although they are specialised into more than 200 different types. Some examples are neurons, red blood cells, adipocytes, ova and spermatozoa.

a) Ovum b) Heart c) Group made up of the mouth, oesophagus, stomach, intestine, pancreas, etc.

In turn, organs group together in systems to perform a coordinated function. Some examples are the respiratory system, the excretory system and the nervous system.

f) Carbon

Atoms bond to form

Carbohydrates

which group together to form

Biomolecules and other substances Lipids

Tissues

Proteins

which group together to form Nucleic acids

Understand, think, search... chemical bond. biomolecules that are polymers.

Water

Phospholipids

Glucose

Iron

Sodium chloride

Potassium

Water

DNA

Cellulose

To overcome this difficulty, we suggest doing the ‘Working with pictures’ activity, which provides other examples, different to those in the picture, that students have to match to the right level.

Organs

3 Which of the following compounds are only found in living matter?

2 What is a polymer? Give some examples of

We believe the difficulty lies in gaining an overall view of the levels and in being able to apply it to real examples.

Cells which group together to form

like

Other substances like water and mineral salts have a simple chemical structure. They are found in both living and non-living matter.

1 Give definitions of bioelement, biomolecule and

which group together to form

Mineral salts

Systems

anayaeducacion.es Go to ‘The composition of living matter’ in your resource bank.

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Students might struggle with the content of this double page, despite having studied most of the levels of organisation of matter in primary school.

d) Protein e) Nucleus

Finally, the human body is made up of a combination of organs and systems, which coordinate to carry out the three vital functions.

Biomolecules are often polymers, chains formed when molecules of the same type, called monomers, bond together. Carbohydrates or sugars, lipids, proteins and nucleic acids (like deoxyribonucleic acid or DNA) are polymers.

Nucleic acids

What level of organisation in the human body do the following parts or groupings belong to?

Tissues group together to form organs, such as the heart, lungs and kidneys, which carry out specific functions.

Biomolecules group together to carry out a function within a cell. They form organelles such as ribosomes and mitochondria.

Nucleic acids contain genetic information, which they transmit to offspring, and control cell functions.

DNA (deoxyribonucleic acid) and RNA (ribonucleic acid) are nucleic acids.

Suggested methodology

Working with pictures

1.4 Organism level Tissues are groups of similar cells that specialise in the same function, and which are sometimes found along with other substances. Some examples are nervous tissue, muscle tissue and epithelial tissue.

Molecules are groups of atoms held together by chemical bonds. Water (H2O), oxygen (O2) and calcium carbonate (CaCO3) are all molecules.

Molecules that make up living beings are called biomolecules and contain a high level of carbon.

Proteins form part of cell structures and regulate and carry out most cell processes. For example, the haemoglobin in red blood cells transports oxygen in the blood, and membrane proteins regulate substance exchange in and out of cells.

F

The word ocus on English karyotic comes from a Greek word meaning kernel or nucleus. The prefix eu- means true, while the prefix pro- means before. What do the words prokaryotic or eukaryotic mean? Which cell is more primitive?

Cells are the structural and functional units of all living beings. That is, they are the smallest part capable of carrying out the three vital functions.

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Answer key

ICT The information on these pages can be supplemented with the resource titled ‘The composition of living matter’, which is available in the resource bank at anayaeducacion.es.

Focus on English This provides a short activity for students to reflect on the root word karyotic and and consider what eukaryotic and prokaryotic might mean.

Understand, think, search...

1 The definitions of the terms are as follows: Bioelements are atoms of chemical elements that make up living matter. Biomolecules are molecules that make up living matter. They are composed of bioelements. Chemical bonds are bonds that form between atoms to make molecules.

2 Polymers are large biomolecules, chains formed when several smaller molecules of the same type, called monomers, bond together. Examples of polymers include cellulose and starch, which are formed of thousands of glucose molecules bonded together, and protein, which is formed of hundreds of amino acids bonded together.

3 Organic biomolecules are only found in living matter: DNA, phospholipids, glucose and cellulose.

Working with pictures In this activity, students have to identify each example in the picture and match it to the correct level of organisation.

Atomic level: carbon.

Molecular level: glucose.

Cellular level: mitochondrion, ovum.

Organ level: heart.

System level: digestive system made up of the mouth, oesophagus, stomach, intestine, pancreas, etc.

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The human cell (I)

Unit 1

THE HUMAN CELL Structure of a eukaryotic animal cell Plasma membrane

Cytoplasm

2.2 The nucleus

The human being is a multicellular organism. It is made up of cells which have very different shapes and sizes. Generally, human cells have three basic parts: the plasma membrane (or cell membrane), the nucleus and the cytoplasm.

2.1 The plasma membrane

The nucleus

The nucleus is a large spherical structure. It contains the genetic material (DNA) which organises the cell’s activity.

The nucleus is made up of the following parts:

The cell membrane is a thin layer that surrounds and protects the cell and regulates exchanges of substances with the surrounding environment.

➜ The nuclear membrane. It contains nuclear pores

The cell membrane is made up of lipids. These form a layer, embedded with proteins, around the cell. The functions of the membrane are to:

➜ The chromatin, which is the network of all the DNA

Nucleus

➜ Detect changes in the environment and allow the

Chromatin

Suggested methodology

which allow substances to be exchanged between the nucleus and the cytoplasm.

➜ The nucleoplasm. It is made up of a thick, aqueous

Nuclear pores

liquid which contains the genetic material or DNA. fibres and proteins. When the cell divides, the chromatin fibres roll up and become compacted, forming structures called chromosomes which are visible under a microscope.

➜ Protect the cell and separate its contents from the outside environment.

Nuclear membrane Nucleolus

➜ The nucleolus is a spherical structure inside the

Chromosomes (condensed chromatin)

nucleus where the component parts of ribosomes (a type of cell organelle) are made.

cell to respond to these changes in an appropriate way.

➜ Regulate the exchange of substances with the environment. The transfer of substances across the cell membrane takes place in different ways and depends on the size of the substance.

Small substances, such as oxygen, can cross the membrane on their own, medium-sized substances cross the membrane with the help of proteins, and large substances cannot cross the cell membrane. Instead, large substances reach the inner part of the cell by endocytosis. In this process the cell wall folds inwards to bring the substance into the cell.

Cell organelles

Cell membrane Carbohydrates

Understand, think, search...

1 Give a definition of cell.

r

terio

Ex

2 What are the functions of the plasma membrane?

3

Proteins

rior

te

In

Lipids

Although animal cells are usually shown as being round, the cells in our bodies have a variety of different shapes. Look for pictures of different types of cell in the human body and draw them in your notebook. Label the three structures they have in common: • the plasma membrane

4

anayaeducacion.es Not all cells are the same, and they do not have the same cellular organisation.

Remind yourself of the types of cellular organisation in living beings by going to ‘Prokaryotic and eukaryotic cells’ in the resource bank. What type of organisation do the following cells have? a) A protozoan

c) The cell in the picture is round, so we can calculate its volume like we would for a sphere. What is its volume? What is the volume of its nucleus?

d) An insect

b) A fungus

e) A bacterium

c) An alga

f) A pine tree

5 Draw a cell nucleus in your notebook, then label its parts and write what their functions are.

6 What two structural states can a nucleus be in?

7 As you already know, cells are microscopic in size. To measure them we use a unit called the micrometre or micron (μm).

On this first double page of the section, we look in detail at two fundamental components of the cell: the membrane and the nucleus. We suggest students copy the illustrations on these pages into their notebooks. We also recommend showing them a video or animation to help them better understand the functions of these components. Students might be motivated by doing a practical activity in the laboratory.

1 = 0.001 mm = 0.000 001 m

• the nucleus

a) Use the bar scale to calculate the diameter of the cell in micrometres.

• the cytoplasm.

b) Find the nucleus in this cell. What is its diameter?

anayaeducacion.es Go to ‘Transport through the membrane’ in your resource bank.

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Understand, think, search...

anayaeducacion.es Go to ‘The size of a cell’ in your resource bank.

5 μm

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ICT

Answer key Understand, think, search...

Activity 3 asks students to search for information, specifically for different types of cell in the human body, to make them aware of the huge variety of cell shapes.

1 A cell is the structural and functional unit of all living beings, that is, it is the smallest part of a

For activity 4, students have to look at the resource t i t l e d ‘ P ro k a r yo t i c a n d e u k a r yo t i c c e l l s ’ a t anayaeducacion.es, and then say what type of organisation different living beings have.

its contents from the outside environment; detecting changes in the environment and allowing the cell to respond to them in an appropriate way; and regulating the exchange of substances with the outside environment.

In addition to the resources mentioned in the activities on these pages, the Anaya Educación website contains the resources ‘Transport through the membrane’ and the ‘The size of a cell’, which expand on the content of these pages.

3 Students have to look up different shaped cells and draw them in their notebooks, labelling

living being capable of carrying out the three vital functions.

2 The cell membrane or plasma membrane is responsible for protecting the cell and separating

the plasma membrane, the cytoplasm and the nucleus. Open answer. They could draw spherical cells, like adipocytes; large spherical cells, like ova; columnar cells, like epithelial cells; cells with a head and a very long tail, like spermatozoa; elongated fusiform cells, like muscle cells; star-shaped cells, like neurons; biconcave cells, like red blood cells; etc.

4 After looking at the resource ‘Prokaryotic and eukaryotic cells’, which is available in the resource bank at anayaeducacion.es, students should answer that bacteria are prokaryotic cells; algae and pine trees have eukaryotic plant cells; and protozoa, fungi and insects have eukaryotic animal cells.

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2

5 Students should draw a nucleus and explain that:

Unit 1

THE HUMAN CELL Structure of a eukaryotic animal cell Plasma membrane

Cytoplasm

2.2 The nucleus

The human being is a multicellular organism. It is made up of cells which have very different shapes and sizes. Generally, human cells have three basic parts: the plasma membrane (or cell membrane), the nucleus and the cytoplasm.

The nucleus

The nucleus is a large spherical structure. It contains the genetic material (DNA) which organises the cell’s activity.

2.1 The plasma membrane

The nucleus is made up of the following parts:

The cell membrane is a thin layer that surrounds and protects the cell and regulates exchanges of substances with the surrounding environment.

➜ The nuclear membrane. It contains nuclear pores

The cell membrane is made up of lipids. These form a layer, embedded with proteins, around the cell. The functions of the membrane are to:

➜ The chromatin, which is the network of all the DNA

Nucleus

• The nuclear membrane contains pores which allow substances to be exchanged between

Nuclear membrane Nucleolus

the nucleus and the cytoplasm.

Chromatin

which allow substances to be exchanged between the nucleus and the cytoplasm.

➜ The nucleoplasm. It is made up of a thick, aqueous

Nuclear pores

liquid which contains the genetic material or DNA. fibres and proteins. When the cell divides, the chromatin fibres roll up and become compacted, forming structures called chromosomes which are visible under a microscope.

➜ Protect the cell and separate its contents from the outside environment.

➜ The nucleolus is a spherical structure inside the

➜ Detect changes in the environment and allow the

• The nucleoplasm contains the genetic material or DNA.

Chromosomes (condensed chromatin)

• The chromatin is the network of all the DNA fibres and proteins and contains genetic

nucleus where the component parts of ribosomes (a type of cell organelle) are made.

cell to respond to these changes in an appropriate way.

➜ Regulate the exchange of substances with the environment. The transfer of substances across the cell membrane takes place in different ways and depends on the size of the substance.

Small substances, such as oxygen, can cross the membrane on their own, medium-sized substances cross the membrane with the help of proteins, and large substances cannot cross the cell membrane. Instead, large substances reach the inner part of the cell by endocytosis. In this process the cell wall folds inwards to bring the substance into the cell.

Cell organelles

Cell membrane Carbohydrates

Understand, think, search...

4

Understand, think, search...

1 Give a definition of cell.

r

terio

Ex

Proteins

rior

te

In

c) An alga

f) A pine tree

are made.

measure them we use a unit called the micrometre or micron (μm).

6 A cell nucleus can be in two states: the resting state and the dividing state. When the cell is

1 = 0.001 mm = 0.000 001 m

• the plasma membrane

a) Use the bar scale to calculate the diameter of the cell in micrometres.

• the cytoplasm.

b) Find the nucleus in this cell. What is its diameter?

anayaeducacion.es Go to ‘Transport through the membrane’ in your resource bank.

5 μm

anayaeducacion.es Go to ‘The size of a cell’ in your resource bank.

33

ICT Activity 3 asks students to search for information, specifically for different types of cell in the human body, to make them aware of the huge variety of cell shapes.

For activity 4, students have to look at the resource t i t l e d ‘ P ro k a r yo t i c a n d e u k a r yo t i c c e l l s ’ a t anayaeducacion.es, and then say what type of organisation different living beings have.

In addition to the resources mentioned in the activities on these pages, the Anaya Educación website contains the resources ‘Transport through the membrane’ and ‘The size of a cell’, which expand on the content of these pages.

2.3 The cytoplasm

Membranous organelles

The cytoplasm is the part of the cell between the plasma membrane and the nuclear membrane.

Mitochondria are oval structures with a double membrane and numerous folds in their internal membrane. They obtain energy for the cell through cellular respiration.

The cytoplasm is formed from a thick, aqueous liquid called cytosol. Cytosol contains different substances and cell organelles.

Cytosol is composed of 70-80 % water and 30-20 % other substances that are dissolved or suspended* within it. These substances include proteins, carbohydrates, lipids, nucleic acids, mineral salts and ions. It is where many of the cell’s vital chemical reactions take place.

F ocus on English The phrase to be suspended in something is a technical phrase meaning that something floats within liquid or air without moving. A similar meaning for to suspend is something that is attached to a high place so that it hangs down. Alternatively to suspend can also be used to mean to stop someone from going to school or work for a short time, especially if they have broken the rules.

Cell organelles are structures that are immersed in the cytoplasm and perform specific functions, like organs.

The Golgi apparatus is a network of flattened sacs that modify the substances that are synthesised in the ER and transport them outside the cell via vesicles.

Non-membranous organelles

Centrioles are two fibre-based cylinders that direct the movement of the cytoskeleton and the chromosomes during cell division.

Ribosomes are small particles that synthesise proteins. They can either be attached to the endoplasmic reticulum or scattered around the cytoplasm.

Create a table describing the following for each cell organelle: What is its function? What would happen if it didn’t exist? What is its relation to the other parts? To find out how to apply this skill, go to anayaeducacion.es. answer the following questions:

0.5 μm

a) Do they show separate cells or the inside of a cell? Explain your answer.

Working with pictures Look at the photo of the cell. What cell structure is coloured green? Describe what you can see in the photo.

The cytoskeleton is a network of fibres that holds the organelles in place and gives the cell its shape. It also plays a part in cell movements (it forms cilia and flagella).

b) Use the bar scale (the black line) to calculate the size of organelle A. c) Draw a picture in your notebook showing what you think this organelle would look like in 3D. Calculate its volume.

anayaeducacion.es Go to ‘Observing cells’ in your resource bank.

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First they must measure the bar scale and the cell. Next they must work out that the bar scale fits approximately 7 times into the cell. They must then multiply this number by the size of the bar scale, 5 micrometres (µm), which tells us that the cell has a diameter of approximately 35 micrometres (µm). a) Using the same procedure, they can work out that the nucleolus spans approximately half the bar scale, which tells us that its diameter is approximately 2.5 micrometres (µm). b) Students will need the formula for the volume of a sphere to calculate both the volume of the nucleus and the volume of the nucleolus: V= 4/3 π r3. By applying this formula, they can work out that the volume of the cell is 22437.91 µm3 and the volume of the nucleolus is 8.177 µm3.

The main difficulty students will have on this second double page of the section will be understanding the functions of each organelle. We recommend linking the functions of the different organelles to an example of a cell need, like the need to repair a piece of plasma membrane. To motivate students and help them remember the information, you could do some kind of game to orally assess whether they can link a picture of the organelle to its name and function.

The parts add up. Each of the structures in a cell performs a specific function, and together they allow the cell to work optimally.

9 Look closely at the micrographs on the right and

calculating the size of the cell in the picture, the size of its nucleus, and the volume of the cell.

Suggested methodology Lysosomes are vesicles that contain digestive enzymes. They digest the particles captured by the cell.

Understand, think, search...

8

7 The aim of this activity is for students to practise the mathematical competence key by

Vesicles are small structures that transport or store substances.

The endoplasmic reticulum (ER) is a network of tubules and sacs that synthesise substances. The rough ER (RER), which has ribosomes attached to its walls, is involved in protein synthesis. The smooth ER (SER), which does not have ribosomes, is involved in the synthesis of lipids.

2.4 Cell organelles There are two types of organelles: non-membranous organelles and membranous organelles.

about to divide, the genetic material, in the form of chromatin fibres, becomes condensed and compacted, forming structures called chromosomes which are visible under a microscope.

The human cell (II)

Unit 1

2 THE HUMAN CELL

information for controlling cell function.

• The nucleolus is a spherical area of the nucleus where the component parts of ribosomes

parts and write what their functions are.

7 As you already know, cells are microscopic in size. To

• the nucleus

Lipids

d) An insect e) A bacterium

6 What two structural states can a nucleus be in?

Although animal cells are usually shown as being round, the cells in our bodies have a variety of different shapes. Look for pictures of different types of cell in the human body and draw them in your notebook. Label the three structures they have in common:

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a) A protozoan b) A fungus

c) The cell in the picture is round, so we can calculate its volume like we would for a sphere. What is its volume? What is the volume of its nucleus?

5 Draw a cell nucleus in your notebook, then label its

2 What are the functions of the plasma membrane?

3

anayaeducacion.es Not all cells are the same, and they do not have the same cellular organisation.

Remind yourself of the types of cellular organisation in living beings by going to ‘Prokaryotic and eukaryotic cells’ in the resource bank. What type of organisation do the following cells have?

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Developing thinking You could use the thinker’s key ‘The parts add up’ for activity 8. This thinker’s key will help students reflect on the function of each cell structure and its importance for the cell as a whole. Tell your students that a resource explaining how to apply this thinker’s key is available at anayaeducacion.es.

ICT To expand on the information on these pages, you can use the resources titled ‘Transport through the membrane’, ‘The size of a cell’ and ‘Observing cells’, which are available in the resource bank at anayaeducacion.es.

When you finish this section, you could do the science workshops on the Anaya Educación website titled ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’, in order to supplement the content and work on skills related to the scientific method.

Answer key Working with pictures In this activity, students have to use what they have learnt to interpret what the picture shows.

The fibres that make up the cytoskeleton are shown in green. The chromatin inside the cell nucleus is shown in blue, in the middle of the picture.

Focus on English This box provides an explanation of the phrase to be suspended in, which students are likely to find difficult.

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Understand, think, search...

Unit 1

2 THE HUMAN CELL

2.3 The cytoplasm

Membranous organelles

The cytoplasm is the part of the cell between the plasma membrane and the nuclear membrane.

Mitochondria are oval structures with a double membrane and numerous folds in their internal membrane. They obtain energy for the cell through cellular respiration.

The cytoplasm is formed from a thick, aqueous liquid called cytosol. Cytosol contains different substances and cell organelles.

Cytosol is composed of 70-80 % water and 30-20 % other substances that are dissolved or suspended* within it. These substances include proteins, carbohydrates, lipids, nucleic acids, mineral salts and ions. It is where many of the cell’s vital chemical reactions take place.

2.4 Cell organelles

F ocus on English

for which an online resource is available at anayaeducacion.es.

The endoplasmic reticulum (ER) is a network of tubules and sacs that synthesise substances. The rough ER (RER), which has ribosomes attached to its walls, is involved in protein synthesis. The smooth ER (SER), which does not have ribosomes, is involved in the synthesis of lipids.

There are two types of organelles: non-membranous organelles and membranous organelles.

The phrase to be suspended in something is a technical phrase meaning that something floats within liquid or air without moving. A similar meaning for to suspend is something that is attached to a high place so that it hangs down. Alternatively to suspend can also be used to mean to stop someone from going to school or work for a short time, especially if they have broken the rules.

8 The aim of this activity is to work on ‘Developing thinking’ using the skill ‘The parts add up’,

Vesicles are small structures that transport or store substances.

Cell organelles are structures that are immersed in the cytoplasm and perform specific functions, like organs.

The Golgi apparatus is a network of flattened sacs that modify the substances that are synthesised in the ER and transport them outside the cell via vesicles.

Non-membranous organelles

Organelle

Lysosomes are vesicles that contain digestive enzymes. They digest the particles captured by the cell.

Understand, think, search...

8

Centrioles are two fibre-based cylinders that direct the movement of the cytoskeleton and the chromosomes during cell division.

Ribosomes are small particles that synthesise proteins. They can either be attached to the endoplasmic reticulum or scattered around the cytoplasm.

The parts add up. Each of the structures in a cell performs a specific function, and together they allow the cell to work optimally.

9 Look closely at the micrographs on the right and answer the following questions:

Working with pictures Look at the photo of the cell. What cell structure is coloured green? Describe what you can see in the photo.

c) Draw a picture in your notebook showing what you think this organelle would look like in 3D. Calculate its volume.

anayaeducacion.es Go to ‘Observing cells’ in your resource bank.

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The cell wouldn’t have energy to carry out its functions

Organelles need energy to carry out their functions

Golgi apparatus (GA)

Modifies the substances synthesised in the ER and packages them into vesicles to be transported or secreted to the outside

The cell wouldn’t be able to secrete, or repair the membrane and other organelles

Modifies the substances produced in the ER

Endoplasmic reticulum (ER)

Produces lipids and proteins

The cell wouldn’t be able to carry out numerous functions performed by proteins and lipids

Produces the proteins and lipids that make up other organelles. Works alongside the GA

Vesicles

They store and transport substances

Substances would be loose in the cytoplasm and could react with one another. In addition, they couldn’t be transported from one part of the cell to another or secreted to the outside

They store lipids and proteins from the ER. Many come from the GA and transport substances to other organelles and the external environment

Lysosomes

They digest captured particles and defective organelles

The cell wouldn’t be able to feed itself or repair certain structures

They come from the GA. Some of their products of digestion are used in the mitochondria to obtain energy

Centrioles

They direct the movement of the chromosomes and the cytoskeleton during cell division

Cell division wouldn’t take place properly

They direct the movement of the cytoskeleton and the chromosomes

Ribosomes

They synthesise proteins

The cell wouldn’t be able to produce proteins and wouldn’t be able to carry out the numerous functions performed by proteins

Some are attached to the ER. They produce the proteins that make up other organelles

Cytoskeleton

Carries out cell movements, gives shape to the organelles and holds them in place

Movements wouldn’t take place in the cell

Centrioles direct its movement during cell division

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Developing thinking You could use the thinker’s key ‘The parts add up’ for activity 8. This thinker’s key will help students reflect on the function of each cell structure and its importance for the cell as a whole. Tell your students that a resource explaining how to apply this thinker’s key is available at anayaeducacion.es.

ICT To expand on the information on these pages, you can use the resources titled ‘Transport through the membrane’, ‘The size of a cell’ and ‘Observing cells’, which are available in the resource bank at anayaeducacion.es.

Focus on English This box provides an explanation of the phrase to be suspended in, which students are likely to find difficult.

Relation to others

They produce energy through cellular respiration

0.5 μm

b) Use the bar scale (the black line) to calculate the size of organelle A.

If it didn’t exist

Mitochondria

Create a table describing the following for each cell organelle: What is its function? What would happen if it didn’t exist? What is its relation to the other parts? To find out how to apply this skill, go to anayaeducacion.es.

a) Do they show separate cells or the inside of a cell? Explain your answer.

The cytoskeleton is a network of fibres that holds the organelles in place and gives the cell its shape. It also plays a part in cell movements (it forms cilia and flagella).

Function

9 This activity requires students to put the mathematical competence into practice. The answers are as follows: a) They show the inside of a cell, because picture A is of a mitochondrion and picture B is of the Golgi apparatus and numerous vesicles. b) Like in activity 7, students must first measure the bar scale and the mitochondrion. Next they must work out that the bar scale fits approximately 5 times into the mitochondrion.

They must then multiply this number by the size of the bar scale, 0.5 micrometres (µm), which tells us that the mitochondrion measures approximately 2.5 micrometres (µm) along its longitudinal axis. c) We could liken a mitochondrion to a cylinder; therefore in order to calculate the approximate volume of the mitochondrion, we need its size along its transversal axis, 1.5 micrometres (µm), and its size along its longitudinal axis, 4.5 micrometres (µm). We use the formula for the volume of a cylinder, V = r2 h π, taking the longitudinal axis as the height (h) and half the transversal axis as the radius (r). The result is V = 7.95 µm3.

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3

4

CELL DIFFERENTIATION

Understand, think, search...

1 Give a definition of tissue.

All the cells in a multicellular organism, such as a human being, are created from one single cell called a zygote, which divides to form an embryo.

At first all the cells in an embryo are the same, but later they take on* different shapes and specific functions. That is, they become specialised. This process is called cell differentiation.

2 What tissue forms part of the sweat glands?

3 Look at the photo. What type of epithelial tissue can you see?

Therefore, although all human cells share basic characteristics (for example, they have the same genetic material), they don’t all have the same shape or the same function.

F ocus on English Take on is a phrasal verb which, in this text, has been used to mean to have a particular quality or appearance.

However, to take something on can also mean to agree to do a new project or extra work. On the other hand, to take somebody on, could mean to employ someone. It can also mean to start a fight or compete with someone, especially if they are more powerful or stronger than you.

Cell differentiation

Unit 1

HUMAN TISSUES

Cell differentiation Differentiation is a combination of changes to the shape and structure of the cell which allow it to specialise in a specific function.

A tissue is a group of cells with a similar shape and structure and which specialise in carrying out the same function.

Human tissues are classified into four basic types: epithelial, connective, muscle and nervous tissues.

4.1 Epithelial tissue Epithelial tissue (or epithelium) is made up of one or more layers of cells that are very close to each other.

Epithelial tissue lines the organs and acts as a protective barrier. There are two types of epithelial tissue:

➜ Covering and lining epithelium. This type of epithelial tissue serves a protective function, lining both the external and the internal surfaces of organs. For example, it lines internal cavities that communicate with the outside environment.

After differentiation has taken place in a multicellular organism, cells that look similar and that carry out the same function group together to form tissues. For example, neurons are star-shaped and have an extension filled with cytoplasm which allows the neuron to receive stimuli and to transmit electrical impulses. Neurons form nervous tissue.

➜ Glandular epithelium. This type of epithelial tissue is made up of cells specialised in producing substances and secreting them onto the epithelial surface. These cells can be scattered around or grouped together as glands, like the sebaceous glands, for example.

Cell differentiation Stem cell

Types of epithelial tissue Simple epithelia

Understand, think, search...

1 In your own words, what is cell differentiation?

2 Are the following statements about cell differentiation true or false?

Cuboidal cells

Squamous cells Glial cells

Stratified epithelia

b) All the cells that make up the human body have the same genetic material.

Columnar cells Glandular epithelium Secreted substances

a) Cells in the human body differentiate because they have different genetic material.

Muscle fibers

Suggested methodology The concept of cell differentiation may seem complicated to students, despite the fact they know from previous years that cells have different shapes, and that their shape is related to the function they perform. However, what students won’t yet know is that all cells come from one initial cell: the zygote. At first all cells are the same, but as the embryo forms, cells undergo this process of cell differentiation, giving rise to all the different kinds of cell that make up the adult body.

Red blood cells Neurons

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Answer key Understand, think, search...

Focus on English This box provides an explanation and extension of the uses of the phrasal verb take on and the differences between ‘take something on’ and ‘take somebody on’.

1 Cell differentiation is a combination of changes to the shape and structure of the cell which allow it to specialise in a specific function. The biological purpose is for zygote cells to acquire different shapes and functions. For example, a neuron’s shape and projections allow it to transmit nerve impulses.

2 a) False, because all the cells in the same human body come from the division of a single cell; they therefore contain the same genetic information. b) True: they all have the same genetic material, although it is not expressed in the same way in all of them.

3 CELL DIFFERENTIATION

4 Understand, think, search...

1 Give a definition of tissue.

All the cells in a multicellular organism, such as a human being, are created from one single cell called a zygote, which divides to form an embryo.

At first all the cells in an embryo are the same, but later they take on* different shapes and specific functions. That is, they become specialised. This process is called cell differentiation.

2 What tissue forms part of the sweat glands?

3 Look at the photo. What type of epithelial tissue can you see?

Therefore, although all human cells share basic characteristics (for example, they have the same genetic material), they don’t all have the same shape or the same function.

F ocus on English Take on is a phrasal verb which, in this text, has been used to mean to have a particular quality or appearance.

However, to take something on can also mean to agree to do a new project or extra work. On the other hand, to take somebody on, could mean to employ someone. It can also mean to start a fight or compete with someone, especially if they are more powerful or stronger than you.

Human tissues (I)

Unit 1

HUMAN TISSUES

Cell differentiation Differentiation is a combination of changes to the shape and structure of the cell which allow it to specialise in a specific function.

A tissue is a group of cells with a similar shape and structure and which specialise in carrying out the same function.

Human tissues are classified into four basic types: epithelial, connective, muscle and nervous tissues.

4.1 Epithelial tissue Epithelial tissue (or epithelium) is made up of one or more layers of cells that are very close to each other.

Epithelial tissue lines the organs and acts as a protective barrier. There are two types of epithelial tissue:

➜ Covering and lining epithelium. This type of epithelial tissue serves a protective function, lining both the external and the internal surfaces of organs. For example, it lines internal cavities that communicate with the outside environment.

After differentiation has taken place in a multicellular organism, cells that look similar and that carry out the same function group together to form tissues. For example, neurons are star-shaped and have an extension filled with cytoplasm which allows the neuron to receive stimuli and to transmit electrical impulses. Neurons form nervous tissue.

➜ Glandular epithelium. This type of epithelial tissue is made up of cells specialised in producing substances and secreting them onto the epithelial surface. These cells can be scattered around or grouped together as glands, like the sebaceous glands, for example.

Cell differentiation Stem cell

Types of epithelial tissue Simple epithelia

1 In your own words, what is cell differentiation? about cell differentiation true or false?

Glial cells

Stratified epithelia

Columnar cells Glandular epithelium Secreted substances

a) Cells in the human body differentiate because they have different genetic material. b) All the cells that make up the human body have the same genetic material.

Cuboidal cells

Squamous cells

Muscle fibers

Red blood cells Neurons

36

Students will be familiar with the concept of tissues from previous years. However, the main difficulty they will have on these pages is taking in the wide variety of tissues that are covered.

Studying the name and function of each tissue therefore becomes a memory exercise, which some students find demotivating. We suggest using the illustrations in the book to point out some characteristics of tissues, like the shape of the cells, the absence of intercellular space in epithelial tissue, or the presence of a matrix in connective tissue.

Understand, think, search...

2 Are the following statements

Suggested methodology

37

This first page of the section sets out the characteristics and main types of epithelial tissue.

Answer key Understand, think, search...

1 A tissue is a group of cells with a similar shape and structure and which specialise in carrying out the same function.

2 Students should link the sweat glands to epithelial tissue, in this case glandular epithelium, given that it is made up of cells specialised in producing substances and secreting them onto the epithelial surface.

3 Students should recognise that it is covering and lining epithelium, specifically stratified epithelium, since it has a top layer of cuboidal cells, under which there is another layer of more elongated cells. This arrangement gives the epithelia a protective function and serves to line surfaces.

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Human tissues (II)

Unit 1

4 HUMAN TISSUES

4.2 Connective tissue

4.3 Muscle tissue

Types of muscle tissue Skeletal striated muscle tissue

Types of connective tissue

Connective tissue consists of cells surrounded by fibres and an intercellular substance called a ‘matrix’.

Reticular connective tissue Fibres

Cells surrounded by lots of fibres

Connective tissue supports and connects organs and other tissues in the body. There are various types:

➜ Reticular connective tissue. This tissue has an Adipose tissue

extensive gel-like matrix containing abundant fibres. It fills the space between organs, keeping them in place, and forms tendons.

➜ Adipose tissue. This tissue has a matrix containing low levels of intercellular substance. Its cells store fat as an energy reserve and for thermal insulation.

It is found under the skin.

Fat cells or adipocytes with low levels of intercellular substance

➜ Cartilaginous tissue. Cartilage has a solid and elastic matrix. It covers the joints to prevent wear.

An example is ear cartilage.

Cartilaginous tissue

Muscle tissue is made up of elongated cells that group together to form muscle fibres and that are able to contract and relax. It is the tissue responsible for body movement.

There are three types of muscle tissue:

➜ Skeletal striated muscle tissue. This tissue forms the

Cardiac striated muscle tissue

the walls of the heart. It is similar to skeletal striated muscle tissue, but its cells only have one nucleus and it contracts involuntarily.

solid and hard, owing to the presence of calcium salts. It forms bones.

➜ Blood. Blood has a liquid matrix called plasma, Chondrocytes

which has blood cells suspended in it (red blood cells, white blood cells and platelets).

Osseous tissue (Bone)

Understand, think, search...

4 What type of connective tissue can you see in each of the following pictures?

Bone cells or osteocytes surrounded by a solid matrix

These pages set out the characteristics of connective tissue, muscle tissue and nervous tissue, showing the different types of each one.

➜ Smooth muscle tissue. This tissue is found in the walls of various organs, like the stomach and the bladder. It contracts involuntarily. The cells that make it up only have one nucleus.

Muscle fibres that are similar to striated muscle, but with only one nucleus.

Smooth muscle tissue

➜ Osseous (bone) tissue. The matrix of this tissue is Solid and elastic matrix

Suggested methodology

Multinucleated muscle fibre.

muscles of the locomotor system and can be moved voluntarily. The cells that make it up have several nuclei.

➜ Cardiac striated muscle tissue. This tissue forms

4.4 Nervous tissue Nervous tissue is the main component of all the structures in the nervous system.

It consists of neurons, which are star-shaped cells that specialise in collecting and transmitting information, and glial cells, which are responsible for neuron nutrition, defence and support.

Muscle cells with only one nucleus.

Nervous tissue Understand, think, search...

Neuron

Blood

5

The mirror. Go to anayaeducacion.es to find out how to apply this thinker’s key, and draw a table comparing the different types of muscle tissue.

6 Compare the tissue shown below to the diagrams on these pages. What type of tissue is it? How do you know?

Blood plasma White blood cells Red blood cells Platelets Glial cells anayaeducacion.es Go to ‘A dichotomous key for identifying tissues’ in your resource bank.

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Developing thinking Students can access the resource titled ‘The mirror’ at anayaeducacion.es to learn the basics for applying this thinker’s key in activity 4.

Given the difficulty of remembering this content, we recommend working with pictures and illustrations of the different types of tissue, so students become familiar with them and are able to identify them. You could also do an experiment to observe tissues and use a dichotomous key to identify them, for which a resource is available in the resource bank at anayaeducacion.es.

Identifying different human tissues using a dichotomous key is a very useful activity that can greatly help students understand the characteristics of the tissues they have studied. We suggest students note down all the steps of the key and the characteristics they observe in each case.

With this information, they can make a factsheet on each tissue, which they can supplement with drawings of their observations and information about the tissue’s function and location in the human body.

ICT The resource titled ‘A dichotomous key for identifying tissues’ is available in the resource bank to help with the different types of human tissue.

Answer key Understand, think, search...

4 Students have to identify tissues from photographs.

The first micrograph shows adipose tissue, characterised by a matrix containing low levels of intercellular substance and cells full of white fat. The second shows osseous tissue, which has a solid and hard matrix owing to the presence of calcium salts, arranged concentrically around the osteocyte.

5 In this activity, we suggest using the thinker’s key ‘The mirror’. This will allow students to compare the different types of muscle tissue so they can reflect on their similarities and differences while also working on the ‘Developing thinking’ competence. They could make several comparisons, always between two types:

Smooth muscle tissue

Cardiac striated muscle tissue

Distinguishing characteristics

Similarities

Distinguishing characteristics

Muscle fibres without striations

Formed of muscle fibres with only one nucleus

Muscle fibres with striations

Walls of organs: Stomach, bladder, etc.

Involuntary contraction

Walls of the heart

Smooth muscle tissue

Skeletal striated muscle tissue

Distinguishing characteristics

Similarities

Distinguishing characteristics

Muscle fibres without striations with only one nucleus

Formed of muscle fibres

Muscle fibres with striations and several nuclei

Involuntary contraction

Movement, voluntary contraction

Walls of organs: Stomach, bladder, etc.

Muscles of the locomotor system

Skeletal striated muscle tissue

Cardiac striated muscle tissue

Distinguishing characteristics

Similarities

Distinguishing characteristics

Muscle fibres with several nuclei

Formed of muscle fibres with striations

Muscle fibres with only one nucleus

Movement, voluntary contraction

Involuntary contraction

Muscles of the locomotor system

Walls of the heart

6 Students must use their observation skills to work out which of the illustrated tissues is shown in the micrograph. We can see non-striated muscle fibres with only one nucleus, so it is smooth muscle tissue.

26

5 As we have just seen, cells of the same kind are organised into tissues.

In turn, different tissues are organised into more complex structures called organs, which form coordinated systems.

5.1 Organs Understand, think, search...

1

Organs and systems

Unit 1

ORGANS AND SYSTEMS

Puzzles. Form groups in your class and share out the topics to be researched. Each group will research a specific organ (brain, heart, stomach, small intestine, etc.) with a focus on the following: a) What is its function? b) What tissues is it made of? c) What type of cells make up these tissues?

The organs of the human body are made up of several tissues that work together to perform a specific function.

For example, the heart pumps blood, the kidneys clean blood, and the lungs exchange gases.

5.2 Systems

5.3 The internal environment One characteristic of multicellular organisms, like human beings, is that most of their cells are not in direct contact with the external environment. This means that they cannot exchange substances (gases, nutrients, waste, etc.) with it, as unicellular organisms do. To solve this problem, they have developed an internal environment.

The internal environment is the fluid that bathes all the organism’s cells. It is connected to the external environment by the blood. Cells take the nutrients and oxygen they need from the internal environment, and discharge the waste they produce into it.

1 Which of the following functions does the internal environment perform? a) It acts as a vehicle substance exchange.

Suggested methodology

for

b) It provides thermal insulation.

Systems are groups of organs that work together to perform a shared activity.

When the different systems work as a whole, the organism is able to perform the three vital functions (nutrition, interaction and reproduction).

Systems and the vital functions

Homeostasis

c) It protects surrounds.

Homeostasis is all the physiological processes that keep the internal environment stable.

The organism achieves this balance thanks to its different organs and systems. This process of regulation prevents changes in the internal environment that would be fatal for cells.

External environment

For interaction

For reproduction

2

ORGANISM

Blood

the

cells

it

Although the systems involved in each vital function are repeatedly studied from primary school onwards, some students forget that the nutrition function is not carried out by the digestive system alone.

The What If What would happen to our bodies if the internal environment didn’t exist?

Learn how to apply this thinker’s key at anayaeducacion.es.

C

Food

Nutrients

For nutrition

Digestive

Understand, think, search...

Technology

REATE The human body and its systems often offer inspiration to robotics designers. Use one of the systems of the human body as inspiration to design a plan for a sensor system.

Respiratory Nervous

Skeletal

Nutrients

Female

O2 CO2

Circulatory

Oxygen (O2)

Tissue cells Carbon dioxide (CO2)

Muscular

Excretory

Male

Lymphatic

Internal environment

Working with pictures

Waste

Endocrine

Waste Urine and sweat

anayaeducacion.es Go to ‘Organs and systems of the human body’ in your resource bank.

40

Look at the diagram showing how the internal environment works. Based on this diagram, write a description of how food, oxygen, carbon dioxide and waste are exchanged between the internal environment and the external environment.

41

Cooperative learning Students have access to the resource titled ‘Puzzles’, which explains this cooperative learning skill to help them apply it more easily in the classroom in activity 1.

For activity 2, students can go to anayaeducacion.es to find the information they need to apply the thinker’s key ‘The What If’.

ICT For a more detailed look at the content covered on these pages, see the resource titled ‘Organs and systems of the human body’ at anayaeducacion.es.

Create This cross-curricular activity with technology gets students to plan a sensor system using the complex systems of the human body as inspiration. There is a worksheet in the Language Bank to support this activity.

Some students who are very familiar with which systems perform each function might feel somewhat confused to learn that our body has another two systems, the lymphatic system and the endocrine system, that they haven’t studied before and the purpose of which they don’t know.

In order to link the content of this section to the content of the previous section, you could ask students to say which tissues they think make up certain organs or systems.

Answer key Understand, think, search...

1 For this activity, with the cooperative learning icon next to it, students have to form groups in order to research specific organs and answer questions about them. Below are the combined answers to a), b) and c):

• Brain. Function: Analyses sensory information and coordinates the motor response. Is responsible for memory, volition and intelligence. Tissues: nervous tissue, and at the bloodbrain barrier epithelial tissue which restricts the passage of substances from the blood.

Cells: neurons and glial cells. At the blood-brain barrier there are endothelial cells and astrocytes.

• Heart. Function: Pumps blood through the pulmonary circuit and the systemic circuit.

Tissues: myocardium (cardiac muscle tissue), endocardium (endothelial epithelial tissue) and pericardium (epithelial tissue). Controlled by nervous tissue. Cells: muscle fibres (cardiomyocytes), epithelial cells and neurons.

• Stomach. Function: Digests food and converts it into nutrients. Tissues: consisting of four layers: mucosa (epithelial and glandular tissue), submucosa (connective tissue), muscular layer (smooth muscle tissue) and serosa (connective tissue, lined by epithelial tissue).

Controlled by nervous tissue. Cells: covering, lining and glandular epithelial cells, smooth muscle fibres, and neurons.

• Small intestine. Function: Absorbs nutrients and passes them into the blood. Tissues: consisting of four layers: mucosa, submucosa (connective tissue), muscular layer and serosa (connective tissue membrane). Accumulations of lymphoid tissue that extend into the submucosa. Cells: absorptive epithelial cells (enterocytes), goblet cells (produce protective mucin), enteroendocrine cells (produce hormones), Paneth cells (produce antibacterial lysozyme), M cells (phagocytes), regenerative cells, etc.

2 Based on the content of the unit, students should be able to answer that the function of the internal environment is a): it acts as a vehicle for substance exchange.

As an option, the teacher could start to introduce students to concepts they will study in subsequent units, by adding that c): it protects the cells it surrounds, is also correct because the internal environment is in contact with lymph, which is rich in white blood cells and connected with the lymph nodes.

3 In this activity, which uses the ‘Developing thinking’ key, students are asked to use the thinker’s key ‘The What If’ to work out the physiological consequences of a process in the body.

The main ideas that students should consider are: if the internal environment didn’t exist, our bodies would have to be much simpler, like those of some invertebrates (poriferans, cnidarians, etc.), whose cells are in direct contact with the environment, because nutrients and waste would have to be exchanged directly with the environment. An organism like a human being wouldn’t be able to survive without an internal environment, since it wouldn’t be able to transport nutrients to cells or collect their waste. It would also be impossible to achieve homeostasis, so the body would be at the mercy of changes in the environment.

Working with pictures In this activity, we ask students to look at the picture and write an explanatory text. The aim is for them to develop their competence in linguistic communication while working on concepts of the unit.

Exchanges between the external environment and the internal environment take place in different ways depending on the substance involved:

• Nutrients. Food is processed (digested and absorbed) by the digestive system and passes into the bloodstream through the small and large intestines. Blood flows all around the body and distributes nutrients to the internal environment of all the tissues. Cells take the nutrients they need to build their structures and perform their functions from the internal environment.

27

5 As we have just seen, cells of the same kind are organised into tissues.

In turn, different tissues are organised into more complex structures called organs, which form coordinated systems.

5.1 Organs Understand, think, search...

1

• Oxygen is captured by the respiratory system, from where it passes into the bloodstream

Unit 1

ORGANS AND SYSTEMS

Puzzles. Form groups in your class and share out the topics to be researched. Each group will research a specific organ (brain, heart, stomach, small intestine, etc.) with a focus on the following: a) What is its function? b) What tissues is it made of? c) What type of cells make up these tissues?

The organs of the human body are made up of several tissues that work together to perform a specific function.

For example, the heart pumps blood, the kidneys clean blood, and the lungs exchange gases.

5.2 Systems

The internal environment is the fluid that bathes all the organism’s cells. It is connected to the external environment by the blood. Cells take the nutrients and oxygen they need from the internal environment, and discharge the waste they produce into it.

Understand, think, search...

1 Which of the following functions does the internal environment perform? a) It acts as a vehicle substance exchange.

for

• Carbon dioxide produced in cellular respiration is released by cells into the internal

b) It provides thermal insulation.

Systems are groups of organs that work together to perform a shared activity.

When the different systems work as a whole, the organism is able to perform the three vital functions (nutrition, interaction and reproduction).

Systems and the vital functions

Homeostasis

c) It protects surrounds.

Homeostasis is all the physiological processes that keep the internal environment stable.

The organism achieves this balance thanks to its different organs and systems. This process of regulation prevents changes in the internal environment that would be fatal for cells.

External environment

For interaction

For reproduction

2

ORGANISM

Blood

the

cells

it

The What If What would happen to our bodies if the internal environment didn’t exist?

Learn how to apply this thinker’s key at anayaeducacion.es.

C

Food

Nutrients

For nutrition

Digestive

through the pulmonary alveoli. The circulatory system distributes O 2 to the internal environment that bathes all the cells of the body, and the cells absorb it from there.

5.3 The internal environment One characteristic of multicellular organisms, like human beings, is that most of their cells are not in direct contact with the external environment. This means that they cannot exchange substances (gases, nutrients, waste, etc.) with it, as unicellular organisms do. To solve this problem, they have developed an internal environment.

environment. From there it passes into the bloodstream and is discharged from the body through the pulmonary alveoli of the respiratory system.

Technology

REATE The human body and its systems often offer inspiration to robotics designers. Use one of the systems of the human body as inspiration to design a plan for a sensor system.

• Waste from cell metabolism is released into the internal environment. Lymph transports it to

Respiratory Skeletal

Nervous

Nutrients

Female

O2 CO2

Oxygen (O2)

Circulatory Tissue cells

Carbon dioxide (CO2)

Muscular

Excretory

Male

Lymphatic

Internal environment

Working with pictures

Waste

Endocrine

Waste Urine and sweat

Look at the diagram showing how the internal environment works. Based on this diagram, write a description of how food, oxygen, carbon dioxide and waste are exchanged between the internal environment and the external environment.

anayaeducacion.es Go to ‘Organs and systems of the human body’ in your resource bank.

40

capillaries and from there it passes into the blood vessels, which transport it to the kidneys, where it is filtered out and excreted in urine.

41

Cooperative learning Students have access to the resource titled ‘Puzzles’, which explains this cooperative learning skill to help them apply it more easily in the classroom in activity 1.

For activity 2, students can go to anayaeducacion.es to find the information they need to apply the thinker’s key ‘The What If’.

ICT For a more detailed look at the content covered on these pages, see the resource titled ‘Organs and systems of the human body’ at anayaeducacion.es.

Research project

Unit 1

ct research proje

Investigating healthy habits for the heart Cardiovascular diseases, like arteriosclerosis, heart attack and stroke, are the leading cause of death in Spain and in other developed countries (see table).

project introduction Leading causes of death worldwide Cardiovascular diseases

32.3 %

Cancer

16.3 %

Respiratory diseases

6.5 %

Diabetes

5.8 %

Acute respiratory infections

4.4 %

Dementia

4.4 %

Neonatal death

3.2 %

Diarrhoeal diseases

3 %

Road accidents

2.5 %

Liver diseases

2.3 %

Organising your work and searching for information

STEP 1

Knowing the annual figures for deaths and their causes is a good way to assess how effective a country’s health system is. These figures help health authorities take targeted public health measures. For example, if mortality due to heart disease and diabetes shoots up in the space of a few years, health authorities will often launch programmes aimed at encouraging healthy habits to prevent these diseases.

Organising your work Your teacher will split the class into groups of 3 or 4. In your groups, discuss the project you are going to carry out and the methods you could use. Divide up the work among the members of your team.

Share your ideas with the other groups. Discuss the number of people you are going to include in the study, the age range, what lifestyles you will look at, and so on. It is important to select a study sample that is representative of as wide a population demographic as possible.

This will make your conclusions from the study more realistic.

It has been proven that the rise in cardiovascular diseases is directly linked to certain habits and lifestyles. Factors that increase the risk of developing a cardiovascular disease include obesity, smoking, a sedentary lifestyle, high levels of cholesterol in the blood, high blood pressure and diabetes.

Finding and analysing information

Main cardiovascular risk factors

When searching for and selecting information for your project, make sure you use reliable sources. Consult sources in different formats (articles, infographics, graphs, etc.). Analyse information about cardiovascular risk factors, their incidence in the population and their effect on the physiological state of the circulatory system.

Genetic predisposition Age

Alcoholism

project objective

Smoking

Diabetes

Obesity

High blood pressure

Some medications

Poor eating habits

To help you search for information, you could write a list of questions like the ones below:

A sedentary lifestyle

does age influence the risk of developing a cardiovascular disease? What about gender? the risk do excess weight and high blood pressure increase of developing a cardiovascular disease? does smoking affect the health of the cardiovascular

✓ How

In this research project, you will be studying cardiovascular risk factors in people of different ages and sexes and with different lifestyles. One of the key objectives is to find out whether adopting certain healthy habits prevents cardiovascular diseases. With the information you have collected, you will prepare a presentation to report the results of your research and the conclusions you have drawn.

✓ Why ✓ How

project steps

This project consists of three stages or steps:

➜ Step 1 (in this unit). Organising your work and searching for the information you need to start your research.

➜ Step 2 (in unit 2). Formulating a hypothesis, carrying out the research and obtaining experimental data.

➜ Step 3 (in unit 3). Analysing the results and drawing conclusions.

Finally, you will prepare a presentation that you can use to report and explain your results in class.

42

system? help prevent cardiovascular do regular physical exercise and a balanced diet diseases? risk factors at the same is it so dangerous to have more than one of these time?

✓ How

✓ Why

43

Enterprising culture Remember to read the document titled ‘Project Keys’, which provides information on the elements and aspects that students work on in this key.

Suggested methodology This research project is on healthy habits for the heart. To help them, students are given basic information about some of the main cardiovascular risk factors alongside tables of figures in which these factors can be quantified. We ask students to study the cardiovascular risk of ten people around them. They must gather information about these people’s lifestyles, formulate a hypothesis about the cardiovascular risk of each person, and test it through experiments. Lastly, we ask them to organise their results and present them to the rest of the class.

The first page of this unit provides an introduction to the project, sets out the project objective, and describes the next steps to allow you to prepare in advance.

In this first step, we recommend splitting students into groups and having them divide up the tasks, allowing them to work on the social aspect of the enterprising culture key. This aspect fosters social experiences, and each student will identify their role within the group, find out what their responsibilities are, and learn that a person working in a group strives for the group’s success, rather than just their own gain (community and common good).

It is important to remind students of the steps of the scientific method, which we covered in the previous unit.

28

r to choose Remembe your portfolio.

resources from

Unit 1

ISE Applying your knowledge

Interpreting pictures

1

3 Copy this drawing and label the cell structures that

Chain of sequences. In your notebook, copy and complete the following chain of sequences about the levels of organisation in living matter.

Find out how to use this graphic organiser at anayaeducacion.es.

correspond to the letters. What is the function of each structure?

I

A

H

They are joined by chemical bonds.

C

G Molecular level Molecules are ? such as ?

Biomolecules are ?

The systems are ? such as ?

The organs are ? such as ?

The tissues are ? such as ?

F

D E

4 Look at the following pictures of tissues and cells and answer the questions: A

Cellular level Cells are ?

Human cells are ? such as ?

B

12 Read the following text and answer the questions: Invented in the 16th century, the microscope is a key tool for studying cells. As more and more powerful microscopes were developed, scientists were able to make discoveries about cellular structure. The ‘power’ of a microscope is its resolution; that is, the smallest distance by which two points can be seperated and still seen as separate points. Optical microscopes use visible light, which passes through the sample and provides an image that is magnified by a set of lenses.

Their resolution is 0.2 μm. Electron microscopes don’t use light, but rather a beam of electrons. These either pass through the sample or bounce off it and are then captured by a screen, where the image appears. Their resolution is 5 μm.

about the cell membrane: a) The cell membrane isolates the cytoplasm from the outside. b) The plasma membrane is formed of a double layer of proteins. c) Medium-sized substances cross the cell membrane freely and without any help. d) Small substances enter the cell by endocytosis.

a) What type of microscope has been used to take these pictures of red blood cells?

8 What is the difference between: a) The nucleus and the nucleolus?

b) If the diameter of a red blood cell is approximately 5 μm, how much magnification does each microscope provide?

b) Chromatin and chromosomes?

C

D

c) The nucleolus and nucleoplasm?

9 List the names of the cell organelles in a table.

Add another column to describe the shape of each organelle, accompanied by a drawing, and another column for its function.

2 Write your own unit summary based on the outline below:

• What is the difference between the atomic and molecular levels of organisation? Include definitions of bioelement and biomolecule.

• Give a definition of cell. What higher levels are cells organised into?

• What is the cell membrane composed of? What are its functions?

• List the parts of a cell nucleus and explain their functions.

a) What types of tissues and cells are shown? b) Link each cell to the tissue it forms part of. c) What is the function of each type of tissue? d) What characteristics of each cell type make them suitable for the function they perform in the human body?

5 What cell structure can you see in the following image? What is it composed of? What level of organisation of living matter does it correspond to?

• Write a list of the membranous organelles and the non-membranous organelles. What is the difference between them? What is the main function of each one?

• Explain what cell differentiation is.

• Name the different types of human tissue. What are the main characteristics of each type?

• Name the different systems in the human body and the function they are involved in.

44

Moving forward

the following correspond to: calcium; kidney; nucleus; group made up of the mouth, oesophagus, stomach, intestine, pancreas, etc.; spermatozoa; protein.

e) The plasma membrane is not present in all cells.

They group together to form organelles such as ?

Summarising

6 State what level of organisation in the human body

7 Copy and correct the following incorrect sentences

B

Atomic level Atoms are ? such as ?

Bioelements are ?

Organism level The human body is ?

They group together to perform the three vital functions.

Review and practise

this unit for

review and PRACT

Organising your ideas

anayaeducacion.es Go to the Science Workshops ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’ in your resource bank.

10 Copy the following sentences and say which tissue they refer to: a) Its matrix is liquid and is called plasma.

13

Many of the body’s cells have names related to the organ they belong to. Search for a picture of each of the following cells and indicate which organ they belong to: hepatocyte, osteocyte, myocyte, chondrocyte.

b) It forms glands, which secrete substances.

Sustainable Development Goals

c) Its matrix is solid and elastic. We find it between the vertebrae and in the ear.

14 Sustainable Development Goal 3 aims to ensure

d) It has a protective function in that it lines cavities. e) It contains low levels of intercellular substance and its cells store fat. f) Its cells transmit nerve impulses. g) Its cells are elongated and it is responsible for body movement. h) Its matrix is solid and contains calcium salts.

11 Why is cell differentiation important? Provide two examples. anayaeducacion.es Go to ‘Key concepts’ and ‘Learn by playing’ in your resource bank.

healthy lives and promote well-being for all. The UN has set numerous targets for this goal. a) In groups, find out about the targets of Goal 3 at anayaeducacion.es. Choose the target that most interests your group, and research it. b)

Prepare a presentation to give to your class about the importance of your group’s chosen target and what could be done to achieve it.

c) Discuss and draw conclusions about the importance of education and research in achieving this goal.

Suggested methodology These final activities give students a chance to review what they have studied over the course of the unit, starting with a diagram and a summary.

Once you have covered the contents of the unit, you could suggest students do the science workshops ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’, available at anayaeducacion.es. These are very simple experiments and students often find them very motivating because they can apply their knowledge and make their own observations.

45

Assessment On these pages, students are given a series of activities to check what they have learnt. We also suggest you remind your students of the importance of compiling work materials from each unit for their portfolio.

Developing thinking Remember to read the document titled ‘Project Keys’ to teach students how to draw a chain of sequences for activity 1.

ICT The following resources are available:

Organising your ideas 1 In this activity, students have to organise information about the organisation of living matter using a chain of sequences.

Atomic level Atoms are the smallest particles into which matter can be divided, such as the hydrogen atom (H) and the oxygen atom (O).

Bioelements are atoms that make up living matter.

They are held together in groups by chemical bonds.

•S cience workshops: ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’ in the resource bank.

Molecular level Molecules are groups of atoms held together by chemical bonds, such as water and the oxygen molecule (O2).

Biomolecules are molecules that make up living beings.

• ‘ Key concepts’, which lets students review the fundamental concepts, and ‘Learn by playing’, which lets students check their learning progress in an entertaining way.

SDG commitment Students have access to videos about the targets of ‘Goal 3’, which provide information that will help them with activity 14.

Enterprising culture Remember to read the document titled ‘Project Keys’, which provides information on the elements and aspects that students work on in this key.

Cellular level Cells are the structural and functional units of all living beings.

Human cells are eukaryotic animal cells like neurons and red blood cells.

They are formed into groups of cellular organelles like mitochondria or ribosomes.

They group together to perform functions.

Organism level The human body is a combination of organs and systems, which coordinate to carry out the three vital functions.

Systems are groups of organs that carry out a shared function, such as the respiratory system and the nervous system.

Organs are groups of tissues that perform a specific function, such as the heart and the kidneys.

Tissues are groups of similar cells that are specialised in a function, such as nervous tissue and muscle tissue.

29

r to choose Remembe your portfolio.

resources from

Unit 1

ISE Applying your knowledge

Interpreting pictures

1

3 Copy this drawing and label the cell structures that

Chain of sequences. In your notebook, copy and complete the following chain of sequences about the levels of organisation in living matter.

Find out how to use this graphic organiser at anayaeducacion.es.

correspond to the letters. What is the function of each structure?

I

A

H

They are joined by chemical bonds.

C

G

Organism level The human body is ?

Molecular level Molecules are ? such as ?

Biomolecules are ?

The systems are ? such as ?

The organs are ? such as ?

The tissues are ? such as ?

F

D E

4 Look at the following pictures of tissues and cells and answer the questions: A

Cellular level Cells are ?

Human cells are ? such as ?

B

12 Read the following text and answer the questions:

the following correspond to: calcium; kidney; nucleus; group made up of the mouth, oesophagus, stomach, intestine, pancreas, etc.; spermatozoa; protein.

Invented in the 16th century, the microscope is a key tool for studying cells. As more and more powerful microscopes were developed, scientists were able to make discoveries about cellular structure. The ‘power’ of a microscope is its resolution; that is, the smallest distance by which two points can be seperated and still seen as separate points. Optical microscopes use visible light, which passes through the sample and provides an image that is magnified by a set of lenses.

Their resolution is 0.2 μm. Electron microscopes don’t use light, but rather a beam of electrons. These either pass through the sample or bounce off it and are then captured by a screen, where the image appears. Their resolution is 5 μm.

about the cell membrane: a) The cell membrane isolates the cytoplasm from the outside. b) The plasma membrane is formed of a double layer of proteins. c) Medium-sized substances cross the cell membrane freely and without any help. d) Small substances enter the cell by endocytosis.

a) What type of microscope has been used to take these pictures of red blood cells?

8 What is the difference between: a) The nucleus and the nucleolus?

b) If the diameter of a red blood cell is approximately 5 μm, how much magnification does each microscope provide?

b) Chromatin and chromosomes?

C

D

c) The nucleolus and nucleoplasm?

9 List the names of the cell organelles in a table.

Add another column to describe the shape of each organelle, accompanied by a drawing, and another column for its function.

2 Write your own unit summary based on the outline below:

• What is the difference between the atomic and molecular levels of organisation? Include definitions of bioelement and biomolecule.

• Give a definition of cell. What higher levels are cells organised into?

• What is the cell membrane composed of? What are its functions?

• List the parts of a cell nucleus and explain their functions.

a) What types of tissues and cells are shown? b) Link each cell to the tissue it forms part of. c) What is the function of each type of tissue? d) What characteristics of each cell type make them suitable for the function they perform in the human body?

5 What cell structure can you see in the following image? What is it composed of? What level of organisation of living matter does it correspond to?

• Write a list of the membranous organelles and the non-membranous organelles. What is the difference between them? What is the main function of each one?

• Explain what cell differentiation is.

• Name the different types of human tissue. What are the main characteristics of each type?

• Name the different systems in the human body and the function they are involved in.

44

Moving forward

e) The plasma membrane is not present in all cells.

They group together to form organelles such as ?

Summarising

6 State what level of organisation in the human body

7 Copy and correct the following incorrect sentences

B

Atomic level Atoms are ? such as ?

Bioelements are ?

They group together to perform the three vital functions.

Summarising

this unit for

review and PRACT

Organising your ideas

anayaeducacion.es Go to the Science Workshops ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’ in your resource bank.

10 Copy the following sentences and say which tissue they refer to: a) Its matrix is liquid and is called plasma.

13

Many of the body’s cells have names related to the organ they belong to. Search for a picture of each of the following cells and indicate which organ they belong to: hepatocyte, osteocyte, myocyte, chondrocyte.

b) It forms glands, which secrete substances.

Sustainable Development Goals

c) Its matrix is solid and elastic. We find it between the vertebrae and in the ear.

14 Sustainable Development Goal 3 aims to ensure

d) It has a protective function in that it lines cavities. e) It contains low levels of intercellular substance and its cells store fat. f) Its cells transmit nerve impulses. g) Its cells are elongated and it is responsible for body movement. h) Its matrix is solid and contains calcium salts.

11 Why is cell differentiation important? Provide two examples. anayaeducacion.es Go to ‘Key concepts’ and ‘Learn by playing’ in your resource bank.

healthy lives and promote well-being for all. The UN has set numerous targets for this goal. a) In groups, find out about the targets of Goal 3 at anayaeducacion.es. Choose the target that most interests your group, and research it. b)

Prepare a presentation to give to your class about the importance of your group’s chosen target and what could be done to achieve it.

c) Discuss and draw conclusions about the importance of education and research in achieving this goal.

45

Assessment On these pages, students are given a series of activities to check what they have learnt. We also suggest you remind your students of the importance of compiling work materials from each unit for their portfolio.

Developing thinking Remember to read the document titled ‘Project Keys’ to teach students how to draw a chain of sequences for activity 1.

ICT The following resources are available: •S cience workshops: ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’ in the resource bank.

• ‘ Key concepts’, which lets students review the fundamental concepts, and ‘Learn by playing’, which lets students check their learning progress in an entertaining way.

SDG commitment Students have access to videos about the targets of ‘Goal 3’, which provide information that will help them with activity 14.

Enterprising culture Remember to read the document titled ‘Project Keys’, which provides information on the elements and aspects that students work on in this key.

2 This activity asks students to write a summary of the key points of the unit.

• Atoms are the smallest particles into which matter can be divided while retaining its properties, for example, the hydrogen atom (H) and the oxygen atom (O). Bioelements are atoms that make up living matter. Molecules are groups of atoms held together by chemical bonds, for example, the water molecule (H2O) and the oxygen molecule (O2). Biomolecules are molecules that make up living beings.

• A cell is the structural and functional unit of all living beings, that is, it is the smallest part of living matter capable of carrying out the three vital functions. Cells groups together to form tissues, which are groups of similar cells that are specialised in a function, for example, nervous tissue and muscle tissue. Tissues form organs, which are groups of tissues that perform a specific function, for example, the heart and the kidneys.

• The cell membrane or plasma membrane is made up of lipids. These form a layer, embedded with proteins, around the cell. The functions of the membrane are: to protect the cell and separate its contents from the outside environment; to detect changes in the environment; and to regulate the exchange of substances with the environment.

• The parts of a cell nucleus are: the nuclear membrane, which contains nuclear pores that allow substances to be exchanged between the nucleus and the cytoplasm; the nucleoplasm, which is made up of an aqueous liquid containing the genetic material or DNA; the chromatin, which is a network of fibres containing the cell’s DNA together with proteins; and the nucleolus, a spherical area of the nucleus where the component parts of ribosomes are synthesised.

• The non-membranous organelles are: – Centrioles, two fibre-based cylinders that direct the movement of the cytoskeleton and the chromosomes during cell division.

– Ribosomes, the function of which is to synthesise proteins.

– The cytoskeleton, which is a network of filaments and fibres that plays a part in cell movements, holds the organelles in place and gives the cell its shape.

The membranous organelles are: – Mitochondria, oval organelles with a double membrane that are responsible for obtaining energy through cellular respiration.

– Vesicles, small compartments that store or transport substances.

– The endoplasmic reticulum (ER), a network of tubules and sacs that synthesise substances: proteins (rough ER, thanks to the ribosomes attached to it) and lipids (smooth ER).

– The Golgi apparatus, a network of flattened sacs that modifies the substances synthesised in the ER and packages them into vesicles to be transported outside the cell.

– Lysosomes, which are vesicles containing digestive enzymes for digesting substances captured by the cell.

• Differentiation is a combination of changes to the shape and structure of cells which allow them to specialise in a specific function. All the cells in multicellular organisms come from one initial cell: the zygote. At first all cells are the same, but as the embryo forms, cells undergo this process of cell differentiation, giving rise to all the different kinds of cell that make up the adult body.

• The tissues that make up the human body are: 1. Epithelial tissue, which is made up of one or more layers of cells that are very close to each other, the types being covering and lining epithelium, which lines the organs and acts as a protective barrier, and glandular epithelium, which secretes substances; 2. Connective tissue, which is made up of cells surrounded by intercellular fibres and/or substances that they synthesise themselves, the types being reticular connective tissue, which fills the space between organs and forms tendons; adipose tissue, which stores fat; cartilaginous tissue, which covers the joints and forms certain structures, like the ear; osseous (bone) tissue, which forms bones; and blood, which transports substances throughout the body; 3. Muscle tissue, which is made up of elongated cells that form muscle fibres, and which is responsible for body movement; and 4. Nervous tissue, which is made up of neurons, cells specialised for transmitting information via nerve impulses, and support cells known as glial cells.

• The systems that make up the human body are: the digestive system, the respiratory system, the circulatory system, the excretory system and the lymphatic system, which are involved in the nutrition function; the nervous system, the endocrine system, the skeletal system and the muscular system, which are involved in the interaction function; and the male and female reproductive systems, which are involved in the reproduction function.

30

r to choose Remembe your portfolio.

resources from

Unit 1

ISE Applying your knowledge

Interpreting pictures

1

3 Copy this drawing and label the cell structures that

Chain of sequences. In your notebook, copy and complete the following chain of sequences about the levels of organisation in living matter.

Find out how to use this graphic organiser at anayaeducacion.es.

correspond to the letters. What is the function of each structure?

I

such as

C

G

Organism level The human body is ?

Molecular level Molecules are ? such as ?

Biomolecules are ?

?

The tissues are ? such as ?

F

They group together to perform the three vital functions.

D E

4 Look at the following pictures of tissues and cells and answer the questions: A

Cellular level Cells are ?

Human cells are ? such as ?

12 Read the following text and answer the questions:

the following correspond to: calcium; kidney; nucleus; group made up of the mouth, oesophagus, stomach, intestine, pancreas, etc.; spermatozoa; protein.

Invented in the 16th century, the microscope is a key tool for studying cells. As more and more powerful microscopes were developed, scientists were able to make discoveries about cellular structure. The ‘power’ of a microscope is its resolution; that is, the smallest distance by which two points can be seperated and still seen as separate points. Optical microscopes use visible light, which passes through the sample and provides an image that is magnified by a set of lenses.

Their resolution is 0.2 μm. Electron microscopes don’t use light, but rather a beam of electrons. These either pass through the sample or bounce off it and are then captured by a screen, where the image appears. Their resolution is 5 μm.

about the cell membrane: a) The cell membrane isolates the cytoplasm from the outside. b) The plasma membrane is formed of a double layer of proteins. c) Medium-sized substances cross the cell membrane freely and without any help. d) Small substances enter the cell by endocytosis.

a) What type of microscope has been used to take these pictures of red blood cells?

8 What is the difference between: a) The nucleus and the nucleolus?

b) If the diameter of a red blood cell is approximately 5 μm, how much magnification does each microscope provide?

b) Chromatin and chromosomes?

C

D

c) The nucleolus and nucleoplasm?

9 List the names of the cell organelles in a table.

Add another column to describe the shape of each organelle, accompanied by a drawing, and another column for its function.

2 Write your own unit summary based on the outline below:

• What is the difference between the atomic and molecular levels of organisation? Include definitions of bioelement and biomolecule.

• Give a definition of cell. What higher levels are cells organised into?

• What is the cell membrane composed of? What are its functions?

• List the parts of a cell nucleus and explain their functions.

a) What types of tissues and cells are shown? b) Link each cell to the tissue it forms part of. c) What is the function of each type of tissue? d) What characteristics of each cell type make them suitable for the function they perform in the human body?

5 What cell structure can you see in the following image? What is it composed of? What level of organisation of living matter does it correspond to?

• Write a list of the membranous organelles and the non-membranous organelles. What is the difference between them? What is the main function of each one?

• Explain what cell differentiation is.

• Name the different types of human tissue. What are the main characteristics of each type?

• Name the different systems in the human body and the function they are involved in.

44

Moving forward

e) The plasma membrane is not present in all cells.

B

They group together to form organelles such as ?

Summarising

6 State what level of organisation in the human body

7 Copy and correct the following incorrect sentences

H

They are joined by chemical bonds.

The systems are ? such as ?

The organs are

A B

Atomic level Atoms are ? such as ?

Bioelements are ?

?

Interpreting pictures

this unit for

review and PRACT

Organising your ideas

anayaeducacion.es Go to the Science Workshops ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’ in your resource bank.

10 Copy the following sentences and say which tissue they refer to: a) Its matrix is liquid and is called plasma.

13

Many of the body’s cells have names related to the organ they belong to. Search for a picture of each of the following cells and indicate which organ they belong to: hepatocyte, osteocyte, myocyte, chondrocyte.

b) It forms glands, which secrete substances.

Sustainable Development Goals

c) Its matrix is solid and elastic. We find it between the vertebrae and in the ear.

14 Sustainable Development Goal 3 aims to ensure

d) It has a protective function in that it lines cavities. e) It contains low levels of intercellular substance and its cells store fat. f) Its cells transmit nerve impulses. g) Its cells are elongated and it is responsible for body movement. h) Its matrix is solid and contains calcium salts.

11 Why is cell differentiation important? Provide two examples. anayaeducacion.es Go to ‘Key concepts’ and ‘Learn by playing’ in your resource bank.

healthy lives and promote well-being for all. The UN has set numerous targets for this goal. a) In groups, find out about the targets of Goal 3 at anayaeducacion.es. Choose the target that most interests your group, and research it. b)

Prepare a presentation to give to your class about the importance of your group’s chosen target and what could be done to achieve it.

c) Discuss and draw conclusions about the importance of education and research in achieving this goal.

45

Assessment On these pages, students are given a series of activities to check what they have learnt. We also suggest you remind your students of the importance of compiling work materials from each unit for their portfolio.

Developing thinking Remember to read the document titled ‘Project Keys’ to teach students how to draw a chain of sequences for activity 1.

ICT The following resources are available: •S cience workshops: ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’ in the resource bank.

• ‘ Key concepts’, which lets students review the fundamental concepts, and ‘Learn by playing’, which lets students check their learning progress in an entertaining way.

SDG commitment Students have access to videos about the targets of ‘Goal 3’, which provide information that will help them with activity 14.

Enterprising culture Remember to read the document titled ‘Project Keys’, which provides information on the elements and aspects that students work on in this key.

3 The aim of this activity is for students to review the structure of a cell, by copying a drawing into their notebooks and indicating the name and function of the labelled structures.

1. Nucleus. Contains the genetic material (DNA), which controls cell activity.

2. Cell membrane or plasma membrane. Surrounds the cell, protects it and regulates substance exchange with the outside environment.

3. C ytoplasm. Contains many substances and the cell organelles, and is the medium in which many of the cell’s vital chemical reactions take place.

4. Mitochondrion. Obtains energy through cellular respiration.

5. Cytoskeleton. Directs cell movements, gives the cell its shape and holds the organelles in place.

6. G olgi apparatus. Modifies the substances synthesised in the endoplasmic reticulum and packages them into vesicles to be transported outside the cell.

7. Endoplasmic reticulum. The rough endoplasmic reticulum synthesises proteins, thanks to the ribosomes attached to its membrane, and the smooth endoplasmic reticulum synthesises lipids.

8. Vesicle. Stores and transports substances.

9. Ribosome. Synthesises proteins.

4 We ask students to identify the tissues in the pictures based on the characteristics they have studied, and to indicate how the specialisation of their cells helps them perform their functions. a) 1. Epithelial tissue. 2. Reticular connective tissue. 3. Nervous tissue. 4. Muscle tissue. b) Epithelial tissue lines and protects the internal and external surfaces of organs and the organism’s body; reticular connective tissue fills the space between organs, keeping them in place, and forms tendons; nervous tissue transmits information in the form of nerve impulses; and muscle tissue is responsible for body movement. c) Epithelial cells have a regular shape and are arranged with very little space between them, which allows them to cover and line surfaces; these cells and the many fibres surrounding them are able to fill the space between organs; neurons have projections with which they communicate with other neurons, allowing them to transmit information in the form of nerve impulses; muscle cells are elongated and are able to contract and relax, so they can carry out the functions of body movement.

5 The picture shows metaphase chromosomes, the state chromatin is in during cell division.

Chromosomes are made up of DNA, which contains the genetic information, and proteins that help condense it, both in chromatin fibres and in chromosomes. The level of organisation is a large-scale molecular level, known as the macromolecular level, since they are made up of many molecules and form a large structure.

Applying your knowledge 6 Calcium: atomic level; kidney: organ level; nucleus: organelle level; group made up of the mouth, oesophagus, stomach, intestine, pancreas, etc.: system level; spermatozoa: cellular level; protein: molecular level.

7 a) The cell membrane separates the cytoplasm from the outside (it doesn’t isolate it, since it regulates substance exchange with the environment). b) The plasma membrane is formed of a double layer of lipids (not proteins). c) Small (not medium-sized) substances cross the cell membrane freely and without any help. d) Large substances (not small substances) enter the cell by endocytosis. e) The plasma membrane is present in all cells.

8 a) The function of the nucleus is to contain the genetic information that controls cell activity, whereas the function of the nucleolus is to synthesise the component parts of ribosomes.

The nucleus is surrounded by a membrane, whereas the nucleolus does not have a membrane. b) Chromatin is the form DNA is in when the cell is not dividing. Chromosomes are the form DNA is in when the cell is dividing. c) The nucleolus is the area of the nucleus where the component parts of chromosomes are synthesised, whereas nucleoplasm is the aqueous liquid found inside the nucleus.

31

r to choose Remembe your portfolio.

resources from

Unit 1

ISE Applying your knowledge

Interpreting pictures

1

3 Copy this drawing and label the cell structures that

Chain of sequences. In your notebook, copy and complete the following chain of sequences about the levels of organisation in living matter.

Find out how to use this graphic organiser at anayaeducacion.es.

correspond to the letters. What is the function of each structure?

I

such as

C

G Molecular level Molecules are ? such as ?

Biomolecules are ?

?

The organs are ? such as ?

The tissues are ? such as ?

F

They group together to perform the three vital functions.

D E

4 Look at the following pictures of tissues and cells and answer the questions: A

Cellular level Cells are ?

Human cells are ? such as ?

12 Read the following text and answer the questions:

the following correspond to: calcium; kidney; nucleus; group made up of the mouth, oesophagus, stomach, intestine, pancreas, etc.; spermatozoa; protein.

Invented in the 16th century, the microscope is a key tool for studying cells. As more and more powerful microscopes were developed, scientists were able to make discoveries about cellular structure. The ‘power’ of a microscope is its resolution; that is, the smallest distance by which two points can be seperated and still seen as separate points. Optical microscopes use visible light, which passes through the sample and provides an image that is magnified by a set of lenses.

Their resolution is 0.2 μm. Electron microscopes don’t use light, but rather a beam of electrons. These either pass through the sample or bounce off it and are then captured by a screen, where the image appears. Their resolution is 5 μm.

about the cell membrane: a) The cell membrane isolates the cytoplasm from the outside. b) The plasma membrane is formed of a double layer of proteins. c) Medium-sized substances cross the cell membrane freely and without any help. d) Small substances enter the cell by endocytosis.

D

c) The nucleolus and nucleoplasm?

9 List the names of the cell organelles in a table.

Add another column to describe the shape of each organelle, accompanied by a drawing, and another column for its function.

below:

• What is the difference between the atomic and molecular levels of organisation? Include definitions of bioelement and biomolecule.

• Give a definition of cell. What higher levels are cells organised into?

• What is the cell membrane composed of? What are its functions?

• List the parts of a cell nucleus and explain their functions.

a) What types of tissues and cells are shown? b) Link each cell to the tissue it forms part of. c) What is the function of each type of tissue? d) What characteristics of each cell type make them suitable for the function they perform in the human body?

5 What cell structure can you see in the following image? What is it composed of? What level of organisation of living matter does it correspond to?

• Write a list of the membranous organelles and the non-membranous organelles. What is the difference between them? What is the main function of each one?

• Explain what cell differentiation is.

• Name the different types of human tissue. What are the main characteristics of each type?

• Name the different systems in the human body and the function they are involved in. anayaeducacion.es Go to the Science Workshops ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’ in your resource bank.

10 Copy the following sentences and say which tissue they refer to: a) Its matrix is liquid and is called plasma.

13

Sustainable Development Goals 14 Sustainable Development Goal 3 aims to ensure

d) It has a protective function in that it lines cavities.

f) Its cells transmit nerve impulses. g) Its cells are elongated and it is responsible for body movement. h) Its matrix is solid and contains calcium salts.

11 Why is cell differentiation important? Provide two examples. anayaeducacion.es Go to ‘Key concepts’ and ‘Learn by playing’ in your resource bank.

Function They direct the movement of the cytoskeleton and the chromosomes during cell division

Ribosome

Two small spheres

They synthesise proteins

Cytoskeleton

Network of filaments

Plays a part in cell movements, holds the organelles in place and gives the cell its shape

Mitochondrion

Oval with a double membrane

Obtains energy through cellular respiration

Vesicles

Small compartments

They store and transport substances

Endoplasmic reticulum

Network of tubules and sacs

Synthesises proteins (RER) and lipids (SER)

Golgi apparatus

Network of flattened sacs

Modifies the substances synthesised in the ER and packages them into vesicles to be transported outside the cell

Lysosomes

Vesicles containing digestive enzymes

They digest substances captured by the cell

Drawing

Many of the body’s cells have names related to the organ they belong to. Search for a picture of each of the following cells and indicate which organ they belong to: hepatocyte, osteocyte, myocyte, chondrocyte.

b) It forms glands, which secrete substances. c) Its matrix is solid and elastic. We find it between the vertebrae and in the ear.

e) It contains low levels of intercellular substance and its cells store fat.

Shape Two cylinders

b) If the diameter of a red blood cell is approximately 5 μm, how much magnification does each microscope provide?

b) Chromatin and chromosomes?

C

Organelle Centrioles

a) What type of microscope has been used to take these pictures of red blood cells?

8 What is the difference between: a) The nucleus and the nucleolus?

2 Write your own unit summary based on the outline

44

Moving forward

e) The plasma membrane is not present in all cells.

B

They group together to form organelles such as ?

Summarising

6 State what level of organisation in the human body

7 Copy and correct the following incorrect sentences

H

They are joined by chemical bonds.

Organism level The human body is ?

The systems are

A B

Atomic level Atoms are ? such as ?

Bioelements are ?

?

9 In this activity, students have to compile key information about cell organelles into a table.

this unit for

review and PRACT

Organising your ideas

healthy lives and promote well-being for all. The UN has set numerous targets for this goal. a) In groups, find out about the targets of Goal 3 at anayaeducacion.es. Choose the target that most interests your group, and research it. b)

Prepare a presentation to give to your class about the importance of your group’s chosen target and what could be done to achieve it.

c) Discuss and draw conclusions about the importance of education and research in achieving this goal.

45

Assessment On these pages, students are given a series of activities to check what they have learnt. We also suggest you remind your students of the importance of compiling work materials from each unit for their portfolio.

Developing thinking Remember to read the document titled ‘Project Keys’ to teach students how to draw a chain of sequences for activity 1.

ICT The following resources are available: •S cience workshops: ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’ in the resource bank.

• ‘ Key concepts’, which lets students review the fundamental concepts, and ‘Learn by playing’, which lets students check their learning progress in an entertaining way.

SDG commitment Students have access to videos about the targets of ‘Goal 3’, which provide information that will help them with activity 14.

Enterprising culture Remember to read the document titled ‘Project Keys’, which provides information on the elements and aspects that students work on in this key.

10 In this activity, students have to identify tissues based on characteristics they have studied in the unit. a) Blood. b) Glandular epithelial tissue. c) Cartilaginous tissue. d) Covering and lining epithelial tissue. e) Adipose tissue. f) Nervous tissue. g) Muscle tissue. h) Osseous (bone) tissue.

32

r to choose Remembe your portfolio.

resources from

Unit 1

ISE Applying your knowledge

Interpreting pictures

1

3 Copy this drawing and label the cell structures that

Chain of sequences. In your notebook, copy and complete the following chain of sequences about the levels of organisation in living matter.

Find out how to use this graphic organiser at anayaeducacion.es.

correspond to the letters. What is the function of each structure?

I

A

H

They are joined by chemical bonds.

C

G

Organism level The human body is ?

Molecular level Molecules are ? such as ?

Biomolecules are ?

The systems are ? such as ?

The organs are ? such as ?

The tissues are ? such as ?

F

D E

4 Look at the following pictures of tissues and cells and answer the questions: A

Cellular level Cells are ?

Human cells are ? such as ?

12 Read the following text and answer the questions:

the following correspond to: calcium; kidney; nucleus; group made up of the mouth, oesophagus, stomach, intestine, pancreas, etc.; spermatozoa; protein.

Invented in the 16th century, the microscope is a key tool for studying cells. As more and more powerful microscopes were developed, scientists were able to make discoveries about cellular structure. The ‘power’ of a microscope is its resolution; that is, the smallest distance by which two points can be seperated and still seen as separate points. Optical microscopes use visible light, which passes through the sample and provides an image that is magnified by a set of lenses.

Their resolution is 0.2 μm. Electron microscopes don’t use light, but rather a beam of electrons. These either pass through the sample or bounce off it and are then captured by a screen, where the image appears. Their resolution is 5 μm.

about the cell membrane: a) The cell membrane isolates the cytoplasm from the outside. b) The plasma membrane is formed of a double layer of proteins. c) Medium-sized substances cross the cell membrane freely and without any help. d) Small substances enter the cell by endocytosis.

a) What type of microscope has been used to take these pictures of red blood cells?

8 What is the difference between: a) The nucleus and the nucleolus?

b) If the diameter of a red blood cell is approximately 5 μm, how much magnification does each microscope provide?

b) Chromatin and chromosomes?

C

D

c) The nucleolus and nucleoplasm?

9 List the names of the cell organelles in a table.

Add another column to describe the shape of each organelle, accompanied by a drawing, and another column for its function.

2 Write your own unit summary based on the outline below:

• What is the difference between the atomic and molecular levels of organisation? Include definitions of bioelement and biomolecule.

• Give a definition of cell. What higher levels are cells organised into?

• What is the cell membrane composed of? What are its functions?

• List the parts of a cell nucleus and explain their functions.

a) What types of tissues and cells are shown? b) Link each cell to the tissue it forms part of. c) What is the function of each type of tissue? d) What characteristics of each cell type make them suitable for the function they perform in the human body?

5 What cell structure can you see in the following image? What is it composed of? What level of organisation of living matter does it correspond to?

• Write a list of the membranous organelles and the non-membranous organelles. What is the difference between them? What is the main function of each one?

• Explain what cell differentiation is.

• Name the different types of human tissue. What are the main characteristics of each type?

• Name the different systems in the human body and the function they are involved in.

44

Moving forward

e) The plasma membrane is not present in all cells.

B

They group together to form organelles such as ?

Summarising

6 State what level of organisation in the human body

7 Copy and correct the following incorrect sentences

B

Atomic level Atoms are ? such as ?

Bioelements are ?

They group together to perform the three vital functions.

11 Examples of why cell differentiation is important:

this unit for

review and PRACT

Organising your ideas

anayaeducacion.es Go to the Science Workshops ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’ in your resource bank.

10 Copy the following sentences and say which tissue they refer to: a) Its matrix is liquid and is called plasma.

13

Many of the body’s cells have names related to the organ they belong to. Search for a picture of each of the following cells and indicate which organ they belong to: hepatocyte, osteocyte, myocyte, chondrocyte.

b) It forms glands, which secrete substances.

Sustainable Development Goals

c) Its matrix is solid and elastic. We find it between the vertebrae and in the ear.

14 Sustainable Development Goal 3 aims to ensure

d) It has a protective function in that it lines cavities. e) It contains low levels of intercellular substance and its cells store fat. f) Its cells transmit nerve impulses. g) Its cells are elongated and it is responsible for body movement. h) Its matrix is solid and contains calcium salts.

11 Why is cell differentiation important? Provide two examples. anayaeducacion.es Go to ‘Key concepts’ and ‘Learn by playing’ in your resource bank.

healthy lives and promote well-being for all. The UN has set numerous targets for this goal. a) In groups, find out about the targets of Goal 3 at anayaeducacion.es. Choose the target that most interests your group, and research it. b)

Prepare a presentation to give to your class about the importance of your group’s chosen target and what could be done to achieve it.

c) Discuss and draw conclusions about the importance of education and research in achieving this goal.

45

Assessment On these pages, students are given a series of activities to check what they have learnt. We also suggest you remind your students of the importance of compiling work materials from each unit for their portfolio.

Developing thinking Remember to read the document titled ‘Project Keys’ to teach students how to draw a chain of sequences for activity 1.

ICT The following resources are available: •S cience workshops: ‘Observing mucosa cells’ and ‘Studying how transport occurs through the membrane’ in the resource bank.

• ‘ Key concepts’, which lets students review the fundamental concepts, and ‘Learn by playing’, which lets students check their learning progress in an entertaining way.

SDG commitment Students have access to videos about the targets of ‘Goal 3’, which provide information that will help them with activity 14.

Enterprising culture Remember to read the document titled ‘Project Keys’, which provides information on the elements and aspects that students work on in this key.

All the cells in multicellular organisms come from one initial cell: the zygote. In the first phases of embryonic development, all the cells are the same, so they are not specialised for any particular function. Thanks to cell differentiation, they become the different types of cell that make up the different tissues of the adult body, meaning cell functions can be shared out. For example, only muscle cells are able to generate movement in the muscles, and only neurons are able to transmit nerve impulses.

Moving forward 12 The aim of this activity is for students to understand the difference between an optical microscope and an electron microscope, and to compare them by calculating the magnification of each picture. a) The top picture was taken with an optical microscope, whereas the bottom picture was taken with an electron microscope. b) We can calculate the magnification by dividing the apparent size (as measured in the picture) by the actual size. In the case of the optical microscope (top picture), the diameter measured in the picture is 2 mm; divided by 5 µm, this gives us a magnification of 400x. In the case of the electron microscope (bottom picture), the diameter measured in the picture is 1.6 cm; divided by 5 µm, this gives us a magnification of 3 200x.

13 Students have to search for a picture of the following cells and indicate which organ they belong to: hepatocyte (liver), osteocyte (bone), myocyte (muscle) and chondrocyte (cartilage, for example in the ear).

Sustainable Development Goals 14 The SDG activity in this unit aims to educate students about Goal 3: Good health and wellbeing. The activity encourages entrepreneurship, so it has the enterprising culture icon next to it. a) Students have to find out about the targets of this goal, for which they can use the videos available on the Anaya website. The targets of this goal are: Target 3.8 Achieve universal health coverage; Target 3.3 End the epidemics; Target 3.4 Reduce by one third premature mortality; Target 3.9 Reduce the number of deaths and illnesses from hazardous chemicals and pollution; Target 3.7 Ensure universal access to sexual and reproductive health-care services; Target 3.c Increase health financing.

We suggest doing this activity in groups, with each group choosing a target and researching it further. Alternatively, each group could choose three targets and share their findings in class, in order to cover as many targets as possible. b) Open answer. Each group of students must prepare a presentation about their chosen target, explaining its importance and suggesting measures to achieve it. c) We suggest having a final class discussion about the importance of education and research in achieving this goal. Education and research are two major pillars of society and have the potential to solve our problems, in the case of education because we cannot take action on matters we don’t know about and are not being taught about, and in the case of research because it involves gaining an in-depth understanding of problems and their causes and looking for solutions.

33