DNA Replication

Question 1

separation of strands, specific coupling of free nucleic acids

Answer 1

Mechanism of replication

Question 2

In order to replicate, First, the double stranded DNA must

Answer 2

separate, or unwind.

Question 3

is responsible for uncoiling the DNA ahead of the replication fork.

Answer 3

DNA gyrase

Question 4

is responsible for unwinding the DNA at the replication fork.

Answer 4

Helicase

Question 5

is responsible for keeping the DNA unwound after the helicase. ( ) stabilize single-stranded DNA by binding to it.

Answer 5

Single-strand binding protein (SSB)

Question 6

you start making DNA that is complementary to the newly unwound/separated DNA. Note, all biological DNA synthesis occurs from the 5’ to the 3’ end.

Answer 6

2nd step in DNA replication

Question 7

creates short RNA primer that is temporarily attached for DNA polymerase to extend from

gets this started by laying down a short RNA primer on the unwound DNA. The primer is made of RNA, but is complementary to the DNA sequence. Later, this RNA is replaced with DNA.

Answer 7

Primase

Question 8

then takes over and makes DNA that is complementary to the unwound DNA.

Answer 8

DNA polymerase

Question 9

The lagging strand contains

Answer 9

Okazaki fragments.

Question 10

Finally, RNA primers are replaced with DNA by a special DNA polymerase. The Okazaki fragments in the lagging strands are then stitched together by DNA ligase.

Answer 10

3rd step in DNA replication

Question 11

Biological DNA synthesis always proceeds from the

Answer 11

5’ end to the 3’ end.

Question 12

has proof-reading activity, which means it corrects any mistakes (mutations) it makes.

Answer 12

DNA polymerase

Question 13

occurs once every cell generation, during the S phase. (Cell division may occur twice in meiosis, but ( )still occurs once only)

Answer 13

Replication

Question 14

contains one old strand and one new strand.

Answer 14

Newly synthesized DNA

Question 15

DNA replication is?

Answer 15

semi-conservative

Question 16

helps to anneal strands; joins Okazaki fragments

Answer 16

DNA ligase

Question 17

lengthens telomeres of linear eukaryotic DNA

Answer 17

Telomerase

Question 18

The process of DNA replication begins at an ( ) where the molecule’s two strands are separated, producing a replication bubble with two replication forks unzipping the DNA bidirectionally away from the origin.

Answer 18

Origin of replication

Question 19

usually have a single origin of replication for their single, circular DNA.

Answer 19

prokaryotes

Question 20

however, have multiple origins of replication across their numerous linear chromosomes.

Answer 20

eukaryotes

Question 21

which acts to lengthen the telomeres with repetitive sequences, thereby protecting them from loss during replication.

Answer 21

telomerase