2.2-Cells Arise

Question 1

. Describe the replication process of bacterial cells (6 marks)

Answer 1

• Binary Fission
• Circular DNA and plasmids replicate
• Circular DNA attaches to opposite ends of cell membrane
• Bacterial cell grows
• The cell membrane pinches inwards in the middle of the cell
• cytoplasm divides to form two daughter cells (each has a variable number of plasmids)
• A cell wall is formed around each daughter cell.

Question 2

6. How does a Virus Replicate?

Answer 2

1. Virus attaches to a host cell
2. Virus injects its genetic material into the host cell
3. The host cell transcribes and translates the viral genes
4. These proteins form new virus particles
5. The virus particles burst out of the host cell, so the host cell is destroyed