3.6- Prokaryotic cells and viruses

Question 1

What is the function of the cell wall?

Answer 1

Made from murein
Excludes certain substances and protects against mechanical damage and osmotic lysis

Question 2

What is the function of the capsule?

Answer 2

Protects bacterium from other cells and helps groups of bacteria stick together for further protection

Question 3

What is the function of the cell-surface membrane?

Answer 3

Acts as s differentially permeable layer which controls the entry and exit of chemicals

Question 4

What is the function of circular DNA?

Answer 4

Possesses the genetic information for the replication of bacterial cells

Question 5

What is the function of plasmids?

Answer 5

Possess genes that may aid the survival of bacteria in adverse conditions

Question 6

Compare and contrast eukaryotic cells with prokaryotic cells

Answer 6

1. Prokaryotic cells don’t contain a nucleus but eukaryotic cells do
2. DNA is not associated with histones in P cells but it is in E cells
3. P cells-circular DNA, E cells-linear DNA
4. P cells- no membrane bound organelles, E cells-membrane bound organelles
5. P cells- smaller ribosomes than in E cells
6. P cells- may have a capsule, E cells- no capsule
7. P cells- no chloroplasts, E cells- chloroplasts present in plants and algae

Question 7

What are viruses?

Answer 7

A-cellular, non-living particles

Question 8

What is the structure of a virus?

Answer 8

Lipid envelope
Capsid
Matrix
Reverse transcriptase
RNA
Attachment proteins