15. DNA replication

Question 1

DNA replication occurs during this phase of the cell cycle

Answer 1

S phase

Question 2

the origin of replication of DNA is recognized by this group of proteins called

Answer 2

Origin Recognition Complex (ORC)

Question 3

unwinds the double helix

Answer 3

helicase

Question 4

maintain the separation of the parent strands

Answer 4

single-stranded DNA- binding proteins

Question 5

relieve torsional strain the results from helicase-induced unwinding

Answer 5

Topoisomerase

Question 6

Type I topoisomerase

Answer 6

Swivelase

Question 7

Type II topoisomerase

Answer 7

Gyrase

Question 8

Gyrase is inhibited by this antibiotic

Answer 8

Fluoroquinolones

Question 9

synthesizes short segments of complementary RNA primers

Answer 9

Primase

Question 10

elongates the DNA strand by adding new deoxyribonucleotides

Answer 10

DNA polymerase III

Question 11

Direction of synthesis of DNA polymerase III proceeds in this direction

Answer 11

5’ to 3’ direction only

Question 12

this DNA strand is synthesized continuously

Answer 12

leading strand

Question 13

this DNA strand consist of Okazaki fragments

Answer 13

lagging strand

Question 14

mismatched necleotides are removed in DNA replication using

Answer 14

3’–>5’ exonuclease

Question 15

this enzyme fills the gap with deoxyribonucleotides

Answer 15

DNA polymerase I

Question 16

seals the nick by catalyzing the formation of the last phosphodiester bond , requiring hydrolysis of ATP

Answer 16

DNA ligase

Question 17

DNA lesion in
Lynch syndrome (Hereditary nonpolyposis colon cancer)

Answer 17

mismatched strand

Question 18

DNA lesion in

Xeroderma pigmentosum

Answer 18

pyrimidine dimers

Question 19

DNA lesion in

MUTYH- associated polyposis

Answer 19

Base alterations

Question 20

DNA lesion in

SCID , Severe combined Immune Deficiency

Answer 20

Double strand breaks

Question 21

DNA lesion in

breast cancer susceptibility 1 and 2

Answer 21

doubt strand breaks

Question 22

in eukaryotes RNA primers are removed by

Answer 22

RNAse H and FEN 1

Question 23

DNA lesion caused by

errors that escaped proofreading

Answer 23

mismatched strand

Question 24

DNA lesion caused by

exposure to UV light

Answer 24

pyrimidine dimers

Question 25

DNA lesion caused by spontaneous or deaminating compounds

Answer 25

base alterations

Question 26

DNA lesion caused by

ionizing radiation, free radicals, anti-tumor drugs

Answer 26

double strand breaks