Living things unit 1 science 5

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SCIENCE 5.

UNIT 1. LIVING THINGS.

CONTENTS: 1.- Characteristics of living beings.

2.- Vital functions: nutrition, interaction, reproduction.

3.- Cells: parts. Animal cells-plant cells.

4.- Unicellular and multicellular organisms.

5.- Cell, tissue, organ, system 6.- Kingdoms: monera, protoctista, fungi, plantae, animalia 7.- Classification of living beings.

8.- Microscope.

C.E.I.P. SANTA ANA (Madridejos)

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Snake versus chameleon

1.– CHARACTERISTICS OF LIVING BEINGS. In nature we can find two types of things: non-living things (stones, rocks, minerals) and living things (animals, plants…). These living beings have two characteristics: they carry out three vital functions and they are formed by cells.

2.– VITAL FUNCTIONS. These vital functions are nutrition, interaction and reproduction.

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NUTRITION is the process in which living beings get oxygen and nutrients, that they use to get energy and grow. Later they expel waste products.

There are three kind of beings depending on the way they get their food: A.- Producers (plants): they produce their own nutrients from water, minerals, gases…

B.- Consumers (animals): get nutrients from other living beings, (plants or another animals).

C.- Decomposers (bacteria, fungi, worms…): get their food from dead organisms and nonliving organic compounds.

INTERACTION is the process in which living beings get information from the environment and produce different reactions to them.

4 .– Animals have sense organs to get information, a nervous system to coordinate reactions, and locomotor system to move themselves. .– Plants haven’t got sense organs, nervous sytem or locomotor system. They only react to light or water when they grow.

Interaction function in animals and plants.

REPRODUCTION is the process in which living beings produce more beings similar to themselves.

There are two types of reproduction: .– Asexual reproduction: When only one individual produces a new living being. .– Sexual reproduction: when a male and a female produce a new living being.

USEFUL WORDS: .– living being . .– non-living being .– vital function .– nutrition .– interaction .– reproduction .– producer .– consumer .– decomposer .– nutrients .– to grow .– to expel .– waste product .– food chain .– sense organs .– nervous system .– locomotor system .– sexual reproduction – asexual reproduction

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3.– THE CELL. Cells are the smallest components of living beings. Cells have many different forms: they can be rounded in animals. Cells from plants have polygonal-shaped. There are star-shaped from the nervous system, or flat from the skin…

They are very small, and we need some devices as a microscope to watch them. All cells carry out all vital functions (they get food, they interacting with the environment, and they reproduce themselves). We can think that they are very different one each other, but all of them has the same structure.

A CELL is the smallest component of a living being (they are microscopic).

1 Types of cells in the human body

3.1.– PARTS OF A CELL. Cells have different parts. Every part has got a function. .- Membrane: is a biological wall that separates the interior of all cells from the outside environment. It basically protects the cell from outside conditions. .– Cytoplasm: is a thick liquid inside the cell membrane. It is formed by water and other substances. The cytoplasm contains different organelles and the nucleus. .– Organelles: are specialized subunits that has a specific function (produce substances, movement…). .– Nucleus: controls the activities of the cell, and it has the genetic material.

Main parts of an animal cell If the genetic material is inside the nucleus, the cell is called eukaryotic cell.

When the genetic material is floating in the cytoplasm, the cell is called prokaryotic cell.

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PARTS OF A CELL are membrane, cytoplasm, organelles and nucleus.

3.2.– ANIMAL CELL AND PLANT CELL. Cells from plants have a hard cover around the membrane called cell wall offering protection, and it gives a strong structure to plants. They also have a special organelles called chloroplasts to do the photosynthesis.

3 USEFUL WORDS: .– polygonal-shaped .– environment .– cytoplasm .– nucleus .– prokaryotic cell .– chloroplast

.– device .– membrane .– organelles .– eukaryotic cell .– cell wall .– photosynthesis

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4.– UNICELLULAR AND MULTICELLULAR ORGANISMS. Some living beings are composed only by one cell. They are called unicellular organism (or single-celled organism), but when they are formed by lots of cells, they are called multicellular organism. Cells are very small and you can only see them through a microscope. In a human body there are more than ten trillion of them.

In multicellular organisms cells form tissues, organs and systems. .- A tissue is a group of similar cells that carry out a specific function. (muscle cells produce movement). Tissues build organs. .– An organ is made up of different tissues that carry out a task. (heart pumps blood to the body). Organs form systems. .– A system is made up of different organs that work together to carry out a common function (all bones form the skeletal system). .– A multicellular organism is formed by lots of systems working together.

Unicellular organisms are composed only by one cell.

Multicellular organisms are composed by lots of cells.

Amoeba: unicelular organism

Cells form tissues.

Tissues form organs.

Organs form systems.

Systems form multicelular organisms.

Living beings organization

5.– CLASSIFICATION OF LIVING BEINGS. We call biodiversity to the variety of living beings that we can find in our planet. To study this biodiversity we classify all beings in five big groups or five kingdoms. Each kingdom are formed by living beings with similar characteristics.

FIVE KINGDOMS are: monera (or bacteria), protoctista, fungi, plant, and animal kingdom.

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5.1.– MONERA KINGDOM (or bacteria) they are microscopic unicellular organisms (without nucleus: prokaryote) that can live everywhere, even inside our bodies. There are helpful bacteria (in our intestine…) and harmful ones that produce many infections and diseases.

USEFUL WORDS: .– unicellular organism .– tissue -multicellular organisms .– organ .– system .– to carry out .– biodiversity .– five kingdoms .– monera or bacteria .– helpful .– harmful .– diseases

.

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5.2.– PROTOCTISTA KINGDOM is formed by unicellular living beings with a nucleus (eukaryotic) like amoebas, protozoa... and others are multicellular like algae. They live in the water in colonies.

Algae make their own food like plants, the rest of them eat other living things.

paramecium

algae

5.3.– FUNGI KINGDOM. .- Fungi cells have a nucleus (eukaryotic) and cell wall like plants. .– They are unicellular like yeast, or multicellular like mould and mushrooms. .– They don’t have roots, leaves or flowers. .– They don’t have chlorophyll, so they can’t make their own food (het erotrophic). .-They are decomposers, so they grow on mortal remains of living beings. yeast

mushrooms

mould

5.4.– PLANT KINGDOM. .– They contain chlorophyll to produce their own food through the photosynthesis (autotrophic). .- They can’t move from the soil. .- They are multicellular with a nucleus. .– There are two groups: .– Without flowers like moss and fern (they reproduce themselves by spores). .– With flowers, like lemon, orange, almond trees, rose bush…

moss

fern Plants with flowers

5.3.– ANIMAL KINGDOM. .– They are multicellular with a nucleus (eukaryotic), without a wall cell . .– They can’t produce their own food (heterotrophic). .– They can move around. .– There are two groups: vertebrates and invertebrates.

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vertebrate

invertebrate

USEFUL WORDS: .– amoebas .– algae .– mould .– autotrophic .– chlorophyll .– fern

.– protozoa .– yeast .– mushrooms .– heterotrophic .– moss .– vertebrate

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6.– CLASSIFICATION OF LIVING BEINGS. Scientists classify living beings into 5 kingdoms. There are lots of types of organisms in each kingdom, so they divide these kingdoms into smaller groups. The smallest group is the species. A species is a group of similar organisms which can reproduce one with each other.

Scientists name every organism with two words: Genus and Species ( example: a cat is Felis Silvestris).

Another example: the human being: Homo sapiens.

Let’s see its full classification:

Animalia

Chordata

Mammals

Primates

Hominidae

Homo

sapiens

KINGDOM

PHYLUM

CLASS

ORDER

FAMILY

GENUS

SPECIES

One idea to remember these words is to learn the first letter from each word. The letters are: KPCOFGS. If we remember a funny sentence is easier: King Philip Can Only Find Green Socks 7.– THE MICROSCOPE. PARTS. Scientists use different devices to learn about living beings. Many of these beings are so small that it’s impossible to see them with the naked eye, so they have to use the microscope.

A microscope is an instrument used to see objects that are too small for the naked eye Eyepiece: lens that magnifies the image from the objective.

3 Arm

Objectives: lenses to magnify the image from the object.

Stage: surface where we place the material.

Diafragm: to control the light Mirror or lamp: to illuminate the object.

Focus knob: to control the distance between the material and the objective. To focus the ima-

Base.

Human body through the microscope

Normal things through the microscope

USEFUL WORDS: .– kingdom .– class .– family .– species .– eyepiece .– focus

.– phylum .– order .– genus .– microscope .– stage .– mirror or lamp