CELLSTopic 1 Biology 2012

What are living things made of?

Living things are made up of cells

Cells are the building blocks of life

They come in all shapes and sizes.

Some organisms are made up of only one cell and are called uni-cellular.

Others are made up of lots of cells and are called multi-cellular.

Cells work together and carry out the seven life processes that are needed for an organism to stay alive.

Seven life processes aka Characteristics of Living Things

All living things do the following

• Watch the You tube clip to identify the 7 characteristics of living things

• http://www.youtube.com/watch?v=aynclw6TXeE&feature=related

Seven life processes aka Characteristics of Living Things

All living things do the following;

Not musically inclined, try this useful pneumonic.

The Cell Theory

1. All organisms are made up of one

or more cells.

2. The cell is the basic LIVING unit

of organization for all organisms.

3. All cells arise from pre-existing cells.

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6Cells ~ Basic building Cells ~ Basic building blocksblocks

There are 2 main types of cells;

PROKARYOTIC CELLSEUKARYOTIC CELLS

Eukaryotic cells are complexProkaryotic cells are more basic

Prokaryotic CellsAre extremely small

Have simple internal structure

No membrane-bound organelles

No membrane-bound nucleus

Kingdoms they belong to are; Monera (bacteria) Archaea

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Generalised Prokaryotic cell

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Eukaryotic CellsCan be single celled organisms

Can be Multicellular organisms

Have a complex internal structure

Have membrane-bound organelles

Have a membrane-bound nucleus

Kingdoms they belong to are; Plantae Animalia Protista Fungi

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Generalised eukaryotic cell10

Animal cell

Plant cell

Cell Size + SpecialisationCell specialisation refers to cells that have

taken on special features to enable them to carry out their task.

This is critical for multicellular organisms.

Size is an important factor in the functioning of cells

The cell must be able to efficiently remove wastes and obtain its requirements.

The rate of outward movement of wastes and inward movement of requirements will influence the size to which the cell will grow.

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Cell SizeCells are measured in:

Microns μm = 10-6 of a metreNanometres nm = 10-9 of a metre

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Animal and plant cells come in different shapes and sizes, but they all have three basic features orparts known as organelles

Plants + animal Cells

plant cellanimal cell

cytoplasm

cell membrane

Plant cells also have some extra features that make them different to animal cells.

nucleus

Organelles:Taking on Different Jobs

Boundary – plasma membranePower Supply – mitochondria Building Cell Structures – ribosomes Supporting Cell Structures – cytoskeleton Transport with the Cell – endoplasmic

reticulumPackaging & Distribution – golgi apparatusRecycling & Reuse – lysosomes Moving in & out – endocytosis & exocytosisCoordinating cell activities – nucleus

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Specialised structures in plants

Chloroplasts – needed for photosynthesis (contain chlorophyll)

Vacuoles (organelles) – for storage of sugars, minerals, proteins & water. They are much bigger in plants than in animals. Can you think of why this might be?

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Cell MovementCells need to be able to move around in order to meet

their requirements for survival or to perform a specific function.

ACTIVE MOVEMENT Cells can move due to specialised structures such as

FLAGELLA & CILIA

PASSIVE MOVEMENT Cells move about because the medium in which they are

located moves them. For example; blood moves RBC’s

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Flagella

Cilia

A school is made up of an organized system.

Individual pupil

Registration group

Subject class

Year group

School

How is the body organized?

Structure of organismsSimilarly to the school, the structure of multicellular

organisms is based around the following ‘levels’ of organisation:

CELLS TISSUES ORGANS SYSTEMS WHOLE ORGANISM

Ultimately, the survival ability of each organism depends upon the functioning of all its individual cells.

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