2.1.2 Structure of prokaryotic cells and of viruses

Question 1

What are the distinguishing features of prokaryotic cells?

Answer 1

● Cytoplasm lacking membrane-bound organelles
● So genetic material not enclosed in a nucleus

Question 2

Describe the general structure of prokaryotic cells

Answer 2

Question 3

Compare and contrast the structure of eukaryotic and prokaryotic cells

Answer 3

Question 4

Explain why viruses are described as acellular and non-living

Answer 4

Acellular- not made of cells, no cell membrane / cytoplasm / organelles

Non-living-have no metabolism, cannot independently move / respire / replicate / excrete

Question 5

Describe the general structure of a virus particle

Answer 5

1. Nucleic acids surrounded by a capsid (protein coat)
2. Attachment proteins allow attachment to specific host cells
3. No cytoplasm, ribosomes, cell wall, cell-surface membrane etc.
4. Some also surrounded by a lipid envelope eg. HIV

Question 6

Label structure of a virus particle

Answer 6