Chapter 3: DNA Replication

Question 1

Semi-conservative??

Answer 1

• one DNA strand from parental helix acts as the template

- one newly synthesized strand

Question 2

dNTPs are added to the _’ end of the chain

Answer 2

3’ OH

Question 3

DNA is synthesized _’ to _’

Answer 3

5’ to 3’

Question 4

The template for DNA synthesis must be single or double stranded?

Answer 4

• single!

- there must be a strand that extends on past the template

Question 5

What are the primary replication enzymes?

Answer 5

Poly I and Poly III

Question 6

there are __ nt/s in bacteria and - nt/s in humans?

Answer 6

• 850

- 60-90

Question 7

Initiation of Replication:
- Replicator ( OriC in E.coli)
L> DnaA?

Answer 7

• initiator proteins bind.
  L> leads to the denaturation of DNA
  L> binds at 9-bp

Question 8

Initiation of Replication:
- Replicator ( OriC in E.coli)
L> DnaB ?

Answer 8

• helicase….binds to DNA with the help of DnaC
  L> break H-bonds btwn bases
  L>r 13-bp since its rich in A and T

Question 9

Initiation of Replication:
- Replicator ( OriC in E.coli)
L> DnaG???

Answer 9

primase binds….its a DnaG gene product…. DNA polymerase binds

Question 10

What are the three core enzymes of DNA Poly III?

Answer 10

• DNA E
  DNA Q
  HOLE

Question 11

What are the three enzymes of DNA poly I?

Answer 11

• DNA E , DNA Q , DA e

Question 12

Replication fork:

- The double stranded DNA section __ to reveal __ template strands

Answer 12

• opens

ssDNA

Question 13

Replication fork

- Leading strand?

Answer 13

• 5-3 strand synthesized continuously

Question 14

Replication fork

lagging strand?

Answer 14

• 3-5’ strand synthesized discontinuously

Question 15

Eukaryotic Polymerases?

- Pol aplha/primase?

Answer 15

• initiates new strands in replication via primase

L> Poly a adds 10-20 nt of DNA

Question 16

Eukaryotic Polymerases?

-Pol e - epsilon?

Answer 16

• synthesize the leading strand

Question 17

Eukaryotic Polymerases?

- Poly delta?

Answer 17

• synthesizes the lagging strand.

Question 18

Eukaryotic Replicons

- More than 1 ___ per chromosome.

Answer 18

• replication

- bidirectional at each origin.