THE CELL

1. THE CELL As you might imagine the cell is a relatively recent discovery. This is due to the fact that you need special tools in order to see them. Robert Hooke (1635-1702) is given credit for coining the term "cell", as he tried to describe what he saw in a cross section of cork. Natural cork comes from a tree, therefore what Hooke was actually looking at was plant cells.

2. "Cella" is a latin word meaning "a small room". Hooke believed that the cells that he saw resembled the small simple rooms that the monks used to sleep in, and so named them cells. CELL THEORY According to the cell theory , proposed over 150 years ago: * All living things are composed of cells * All cells come from pre-existing cells * Cells are the smallest units of life

3. Most cells are very, very small, so tiny that they can only be seen with the aid of a microscope. Your body is composed of billions of cells! Within your body, cells have different functions. We have blood cells, skin cells, brain cells... and many more. Despite their differences, cells in living organisms for the most part have similar structures and functions. The human body has roughly 85 completely different types of cells. Cells occur in an infinite variety of sizes, shapes, colours. There is no such thing as a "typical cell" But if we did have one it would be 20um in diameter, and have a nucleus. It would also have a cell membrane that surrounds it from it's environment, and would contain many tiny structures that might be thought of as mini organisms called organelles.

4. There are two basic types of cells: Plant Cells and Animal Cells There are many structures within the cell, these are known as organelles. Organelles: Membrane bounded structures that perform a series of specialized tasks.

5. ORGANELLES Nucleus: Main repository of genetic information. Controls the activities of the cell. It is like the central command. Ribosomes: Ribosomes make protein for the cell and cellular functions.

6. Vacuoles: Vacuoles are simple organelles consisting of a large membrane sac. It can enclose many different substances from food particles to waste products. The Vacuole is very important to plant cells. Mitochondria: Mitochondria produce the energy the cell requires to carry out its processes. The mitochondria are the power houses of the cell. Chloroplasts: Chloroplasts are the organelles that are responsible for carrying out photosynthesis. They are the power houses of plant cells.

7. Cell Wall: Plants produce tough rigid cell walls that surround their cell membrane. They are tough enough to withstand tremendous pressure.

8. Cell Membrane: The Cell membrane is one of the most important structures in the cell. It divided the cell into many compartments and separated the cell from the environment. (Skin).

11. Maintains Structure Surrounds the cell Maintains Pressure Surrounds the cell Controls what moves in and out Controls the activities and functions of the cell Center of the Cell Throughout Cell Holds organelles in place Carries out Photosynthesis Inside the Cell Power house of plant cells Inside the Cell Maintains structureof the cell Inside the Cell Transports and stores materials for the cell Inside the Cell Modification of proteins Inside the Cell Food digestion for the cell Inside the Cell Power house of animal cells Inside the Cell Makes proteins for the cell Maintains pressure Inside the Cell Stores materials (food and wastes) Inside the Nucleus Holds genetic information Inside the Cell Aids in cell division

12. http://koning.ecsu.ctstateu.edu/cell/Cell.html http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/P/PlantCell.html http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/A/AnimalCells.html http://www.cellsalive.com/cells/animcell.htm WEBSITES www.cellsalive.com/cells/plntcell.htm http://www.rkm.com.au/CELL/a nimalcell.html