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.
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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.
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