Unit 6, Topic 2: Replication

Question 1

specific nucleotide sequences that signal the beginning of replication

Answer 1

origins of replication

Question 2

Y-shaped structure formed during initiation of replication

Answer 2

Replication fork

Question 3

during replication, this enzyme helps to open up the DNA helix by breaking the hydrogen bonds

Answer 3

helicase

Question 4

enzyme that prevents overwinding of DNA when DNA replication is taking place

Answer 4

Topoisomerase

Question 5

enzyme that synthesizes the RNA primer; the primer is needed for DNA pol to start synthesis of a new DNA strand

Answer 5

Primase

Question 6

short stretch of nucleotides that is required to initiate replication; in the case of replication, the primer has RNA nucleotides

Answer 6

Primer

Question 7

the enzyme required for DNA synthesis

Answer 7

DNAP III

Question 8

enzymes required for DNA repair

Answer 8

DNAP I & II

Question 9

strand that is synthesized continuously in the 5’-3’ direction which is synthesized in the direction of the replication fork

Answer 9

Leading strand

Question 10

during replication, the strand that is replicated in short fragments and away from the replication fork

Answer 10

lagging strand

Question 11

DNA fragment that is synthesized in short stretches on the lagging strand

Answer 11

Okazaki fragments

Question 12

enzyme that catalyzes the formation of a phosphodiester linkage between the 3’ OH and 5’ phosphate ends of the DNA

Answer 12

DNA ligase

Question 13

DNA at the end of linear chromosomes

Answer 13

Telomere

Question 14

enzyme that degrades nucleic acids

Answer 14

Nuclease

Question 15

enzyme that contains a catalytic part and an inbuilt RNA template; it functions to maintain telomeres at chromosome ends

Answer 15

Telomerase

Question 16

type of repair mechanism in which mismatched bases are removed after replication

Answer 16

mismatch repair

Question 17

In which stage of the cell cycle does DNA replicate?

Answer 17

S phase of interphase

Question 18

If an error occurs in DNA replication, how is it fixed?

Answer 18

DNA polymerase proofreading

Question 19

In which model do both copies of DNA have double-stranded segments of parental DNA and newly synthesized DNA interspersed?

Answer 19

dispersive model

Question 20

In which model does the parental DNA remain together, and the newly formed daughter strands are together?

Answer 20

conservative model

Question 21

In which model do each of the two parental DNA strands act as a template for new DNA to be synthesized?

Answer 21

semi-conservative model

after replication, each double-stranded DNA includes one parental or “old” strand and one “new” strand.