Exam 4

Question 1

Which mechanism does DNA replication occur?

Answer 1

semi-conservative

Question 2

Draw the three models of DNA replication

Answer 2

conservative, dispersive, and semi-conservative

Question 3

Describe replication in prokaryotes

Answer 3

replication usually begins at unique point and proceeds in both directions simultaneously

Question 4

What is the sigma structure?

Answer 4

replicating chromosome in prokarotes

Question 5

What are the three main types of DNA polymerase in bacteria?

Answer 5

DNA polymerase I, II, and III

Question 6

What is the role of DNA pol I in bacteria?

Answer 6

plays essential, albeit secondary role in replications, also involved in repairs

Question 7

What is the role of DNA pol II in bacteria?

Answer 7

DNA repair and replication of damaged DNA

Question 8

What is the role of DNA pol III in bacteria?

Answer 8

major replication enzyme also involved in repair

Question 9

Describe the exonuclease activity for DNA pol I

Answer 9

5’ to 3’ exonuclease activity

Question 10

Describe the polymerase activity of DNA pol I, II, and III

Answer 10

5’ to 3’ polymerase activity

Question 11

How does DNA pol I differ from II and III

Answer 11

DNA pol II and III have 3’-5’ exonuclease activity

Question 12

How does DNA polymerase function?

Answer 12

slides along template making new strand by connecting deoxyribonucleasetriphosphates (dNTPs) in a 5’ to 3’ direction

Question 13

T/F: DNA pol can only attach nucleotides in a 5’ to 3’ direction

Answer 13

true

Question 14

How can DNA pol elongate a strand?

Answer 14

from an RNA primer or an existing DNA strand

Question 15

What are the three phases of DNA replication?

Answer 15

initiation
elongation
termination

Question 16

What is the acronym for E. Coli origin of replicaiton?

Answer 16

oriC

Question 17

OriC is about __ base pairs long

Answer 17

275

Question 18

What are the two important sites contained in OriC?

Answer 18

A/T rich region and Fine, 9, bp repeats !!