DNA Synthesis Flashcards

1
Q

DNA replication is initiated at specific sites on DNA called…..

A

Replication origins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the length of Bacterial cell cycle?

A

20-30 minutes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How many replication origins does bacteria have?

A

Single replication origin on their genome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the phases of cell cycle in bacteria?

A

2 phases

S phase + M phase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is length of mammalian cell cycle?

A

16-24 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are phases of mammalian cell cycle?

A

G1, S, G2, M
G stands to Gap
S stands for synthesis
M stands for mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is purpose of G1 phase?

A

It allows cell to prepare for next phase
Allow synthesis of all the extra histones you need for S phase
Synthesis of DNA polymerase
Ensures building blocks for making DNA are present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is purpose of G2 phase?

A

Prepare to condense chromosomes + Allow their segregation in mitosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How many replication origins are present in eukaryotic cells?

A

There are multiple replication origins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What DNA polymerase are present in bacteria + what are their functions?

A

DNA Polymerase I = repair
DNA polymerase II = repair
DNA polymerase III = replication
Others= repair

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What DNA polymerases are present in eukaryotic cells?

A
DNA polymerase alpha= replication 
DNA polymerase beta = repair 
DNA polymerase gamma= mitochondrion 
DNA polymerase delta= replication 
DNA polymerase epsilon = replication
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is purpose of DNA polymerase and what does it require to function?

A

It synthesises DNA
Acts in 5’-3’ direction
Utilises A-T and C-G base pairing to synthesise new DNA strand
Requires DNA template, DNA/RNA primer, dNTP building blocks and Mg2+ ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are dNTPs?

A

Are building blocks of DNA

There are 4 of them => dATP, dCTP, dGTP, dTTP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is purpose of DNA helicase?

A

Separates base pairs producing single strands using ATP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is purpose of topoisomerase?

A

Goes in front of helicase + gets rid of cells in DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is purpose of primase?

A

Lays down some RNA so that DNA polymerase knows where to start replicating

17
Q

What is purpose of DNA binding proteins?

A

Stabilise single stranded DNA, stop it being re-annealed with other parent strand

18
Q

What is purpose of replicative DNA polymerase?

A

Copies parental strand

19
Q

What is purpose of repair DNA polymerase?

A

Repair fragment + takes out RNA so it will be a full DNA strand

20
Q

What is purpose of DNA ligase?

A

Splices fragment together

21
Q

Why is error rate in DNA replication low?

A

Low due to base pairing + proof reading/ editing function of DNA polymerase
Mismatch repair system- corrects most of polymerase errors