WJAC AS Biology - Cell Organisitaion

Cell Organisation

There are two types of cell: prokaryotic cells and eukaryotic cells. Prokaryote cells have a simple structure and were probably the first forms of life on earth. Eukaryotic cells probably evolved from prokaryotic cells around 1000 million years ago. 

Prokaryotic and Eukaryotic cells

An example of a prokaryotic cell is a bacterium. Eukaryotic cells are typical of the great majority organisms including animals and plants.

Prokaryotic Cells

Bacteria and blue-green algae.

No membrane bound organelle.

DNA lies free in the cytoplasm.

No nuclear membrane or ER.

70s Ribosomes.

Cell wall containing murein, made of peptidoglycan. 

Eukaryotic Cells

Found in plants, animals, fungi and protoctists.

Membrane bound organelles.

DNA located on chromosomes.

Distinct membrane-bound organelles.

Cell wall in plants made of cellulose.

Viruses

Viruses cause a variety of infectious diseases in humans, animals and…