DNA replication

Question 1

information is copied during ____ and distributed during ____.

Answer 1

interphase

cell division

Question 2

parts of the cell cyle

Answer 2

G1 to S to G2 to mitosis

Question 3

period of cell growth before the DNA is duplicated

Answer 3

gap one (G1)

Question 4

period when the DNA is duplicated

Answer 4

synthesis phase (S phase)

Question 5

period after DNA is duplicated and cell prepares for division

Answer 5

gap two (G2)

Question 6

G1, S, and G2 make up the

Answer 6

interphase

Question 7

four general characteristics of DNA replication

Answer 7

chemically uni-directional
semi-conservative
spatially bi-directional
semi-discontinuous

Question 8

scientists that proved DNA replication was semi-conservative

Answer 8

meselson and stahl

Question 9

DNA replication occurs in specific nuclear or nucleoid compartments

Answer 9

replication factories

Question 10

the region of DNA that first separates and replication begins

Answer 10

origins of replication

Question 11

DNA replication proceeds in both directions away from the origin of replication

Answer 11

bi-directional replication

Question 12

the point of separation of double-stranded DNA at which incorporation of nucleotides occurs during DNA replication

Answer 12

replication fork

Question 13

where each separated polynucleotide strand serves as a template for the synthesis of a single new complementary strand

Answer 13

semi-conservative replication

Question 14

the synthesis of DNA fragments that occurs in the lagging strand during DNA replication

Answer 14

semi-discontinuous replication

Question 15

the name given to the discontinuous fragments of DNA synthesized in the lagging strand

Answer 15

okazaki fragments

Question 16

five basic steps for DNA replication

Answer 16

1. helicase unwinds parental double helix
2. single stranded binding proteins stabilize unwound DNA
3. leading strand is synthesized continuously in 5’ to 3’ direction by DNA polymerase
4. lagging strand is synthesized discontinuously by RNA primase laying a primer down so DNA polymerase can form an okazaki fragment
5. DNA ligase joins okazaki fragments

Question 17

unwind and stabilize the duplex DNA to form the replication fork

Answer 17

initiation

Question 18

DnaA proteins bind to origin of replication

Answer 18

initiation factors

Question 19

DnaB protein catalyzed the ATP-dependent unwinding of duplex DNA

Answer 19

helicase

Question 20

prevent supercoiling and tangling of DNA during unwinding; binding ahead of the replication fork, nick super coiling DNA, and relaxes stress allowed by uncoiling

Answer 20

topoisomerases

Question 21

prevents re-annealing of the separated single strands, protects against nuclease degradation

Answer 21

ssDNA binding proteins

Question 22

5’ to 3’ synthesis of complementary DNA

Answer 22

replication

Question 23

an RNA polymerase synthesizes a short RNA primer

Answer 23

primase

Question 24

extends the RNA-primed chain and is the main replication enzyme

Answer 24

DNA polymerase III

Question 25

later replaces RNA with DNA and using 3' to 5' exonuclease activity to ensure accuracy

Answer 25

DNA polymerase I

Question 26

joins DNA fragments

Answer 26

DNA ligase

Question 27

subunits of DNA polymerase that use ATP to load DNA into the beta clamp unit

Answer 27

tau gamma beta beta prime

Question 28

hold/guides DNA, opens and closes to allow passage of DNA in DNA polymerase

Answer 28

beta sliding clamp

Question 29

an enzyme that removes nucleotides from the end of a polynucleotide strand

Answer 29

exonuclease

Question 30

subunit of DNA polymerase that performs 5' to 3' polymerase reaction

Answer 30

alpha subunit

Question 31

subunit that performs exonuclease

Answer 31

epsilon subunit

Question 32

what makes up the DNA replicating machine called a replisome

Answer 32

two copies of DNA polymerase III | primosome DNA unwinding proteins

Question 33

contains primase and auxiliary proteins

Answer 33

primosome

Question 34

repair enzymes normally present in cells where they repair low levels of DNA damage

Answer 34

DNA polymerase II and IV

Question 35

bind to sites on opposite side of DNA loop, inhibit helicase and prevent further progression of replication fork (in prokaryotes)

Answer 35

ter binding proteins

Question 36

play a role in replication termination in eukaryotes by preventing the ends of DNA from being lost

Answer 36

telomeres

Question 37

an enzyme that restores telomere sequence

Answer 37

telomerase

Question 38

how does telomerase work

Answer 38

extends the unreplicated end so the lagging strand can be completed