DNA Replication

Question 1

Helicase

Answer 1

Unzips the DNA molecule

Breaks the hydrogen bods

Question 2

Replication fork

Answer 2

Y-shape of DNA that is formed when helicase begins its job

Question 3

Origins of replication

Answer 3

Specific sites where DNA replication begins
Prokaryotes: only one
Eukaryotes: multiple

Question 4

Topoisomerase

Answer 4

Enzyme that attaches to DNA to prevent it from getting tangled

Question 5

DNA polymerase

Answer 5

Enzyme that adds nucleotides to the separate strands; can only add nucleotides to 3’ end so it has to add nucleotides to an RNA primer; type 3 adds nucleotides and type 1 removes the RNA primers

Question 6

RNA primase

Answer 6

Places RNA primers on the DNA; places very few on the leading strand but multiple on the lagging strand because DNA cannot read in the direction of the lagging strand so it needs more help from the primer

Question 7

RNA primers

Answer 7

Short strands of RNA nucleotides; removed by DNA polymerase 1 later

Question 8

Leading strand

Answer 8

Nucleotides are steadily added one by one on this strand because DNA polymerase reads it 5’ to 3’

Question 9

Lagging strand

Answer 9

Made discontinuously because many RNA primers are needed because this strand reads 3’ to 5’; ends up in Okazaki fragments

Question 10

Okazaki fragments

Answer 10

Fragments of DNA created on the lagging strand by the multiple RNA primers

Question 11

DNA ligase

Answer 11

Enzyme that links Okazaki fragments together

Question 12

Semiconservative

Answer 12

CORRECT theory; one daughter strand is from the parents and the other daughter strand is brand new