27 th sept 2007 cells plants and animals are built up of cells stuck together. houses are built up...

27th Sept 2007

CELLS Plants and Animals are built up of Cells stuck together.

Houses are built up of bricks stuck together.

How many cells?Unicellular

Eg.

Multicellular

What is a cell?

All living organisms are composed of cells.

But what exactly is a cell?

CELLS ARE:the smallest unit of living matter.

Cells are small compartments that hold all of the biological equipment necessary to keep an organism alive.

This means that each cell can: it can take in nutrients, convert these nutrients into energy,

carry out specialised functions and reproduce as necessary.

The two Cell types

Activity 1:Learning to draw a plant cell:

You will need: 1 well sharpened pencilEraser

Types of cells

Reading Assignment 1Find and underline on your handout the functions of the following structures: Cell wallCell membraneVacuolesChloroplastsMitochondrion

Cell Structures and Functions:Nucleus Controls reproduction and also

contains the characteristics of the cell.

Cell membrane Surrounds the cell and controls what moves in and out of the cell

Cytoplasm - Jelly like substance where chemical reactions take place and other parts are embedded.

Mitochondria Found only in plant cells where respiration occurs.

Chloroplasts These makes plants green. They contain chlorophyll which is needed for photosynthesis.

Cell wall Gives the cell its shape. The cell's "skeleton".

Vacuoles Where the cell sap is stored.

The differences between animal and plant cells are as follows: Plant Cells Animal CellsChlorophyll in chloroplasts,

No Chlorophyll or chloroplasts,

A cellulose cell wall, No Cellulose cell wall,

Large vacuoles Small or no vacuoles.

Starch Grains Glycogen granules

Review Question

Home -WorkFind out the reasons for the difference s which exists between the plant and animal cells.

Apple 2007