[Unit 3.6] | Prokaryotic Cells & Viruses

Question 1

Name and describe the functions of sub-cellular structures (5) in prokaryotes.

Answer 1

• Cell wall:
» Made of murein
» Prevents the cell from bursting and provides rigidity

• DNA:
> No nucleus
» Single circular DNA molecule which is free floating, not associated with histones and does not contain introns.

• Extra DNA - Plasmids:
» Can be transferred to other prokaryotes
» Tiny & circular

• Slime capsule:
» Prevents drying out
» Makes cell slippery (some bacteria cannot be engulfed by phagocytes due to it)

• Flagellum: Long hair-like projection that rotates to propel the prokaryote.

Question 2

Are virions alive?

Answer 2

• No, they do not perform all the MRS GREN functions of life.

• They cannot replicate outside of host cells.