Session 4-Cell Cycle Flashcards Preview

Semester 1-MCBG > Session 4-Cell Cycle > Flashcards

Flashcards in Session 4-Cell Cycle Deck (10):
1

Which enzyme catalyses DNA replication?

DNA polymerase

2

How is DNA replication driven?

Pyrophosphate hydrolysis

3

What are the three stages of DNA replication?

Initiation
Elongation
Termination

4

What happens during initiation?

The origin of replication is recognised
DNA polymerase is recruited
Primase helps to kick-start reaction

5

What does DNA helicase do?

Unwinds the double helix

6

DNA polymerase extends 3' ends only-what does this lead to? (3)

Leading strand (continuous)
Lagging strand (discontinuous)
Okazaki fragments

7

Which enzyme joins fragments?

DNA ligase

8

What happens in termination?

Two facing replication forks meet and DNA ligase joins the final fragments

9

Why are telomeres needed?

So the primer can prime to it and prevent the shortening of DNA (telomeres are non-coding DNA)

10

How might interfering with telomeres allow the treatment of cancer?

If you can speed up the process of telomere shortening, the cell will eventually senesce and you can then stop cancer cells replicating