Cells!

All living things are made up of cells.
Cells are the smallest working units of all living things.
All cells come from the pre-existing cells through cell division.

Definition:
a cell is the smallest unit that is capable of performing life functions.

example of cells:
Amoeba proteus

Amoeba proteus

Two types of cells:
Prokaryotic
Eukaryotic

Prokaryotic cells:

• Do not have organelles surrounded by membranes.
• Few internal structures
• one celled organisms e.g. bacteria

Eukaryotic cells:

• contain organelles surrounded by membranes
• most living organisms e.g. plant, animal, fungi

Cell wall

• most commonly found in plant cells and bacteria
• surrounds the cell membrane
• rigid structure that maintains the shape, supports and protects cells
• permeable to small molecules and small proteins only

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