DNA replication order, enzymes, & extra

Question 1

helicase function

Answer 1

breaks the hydrogen bonds that hold the complementary bases together

Question 2

primase function

Answer 2

adds the RNA primers

Question 3

DNA polymerase III function

Answer 3

adds new nucleotides to build new DNA strands

Question 4

DNA polymerase I function

Answer 4

removes RNA primers and replaces them with DNA nucleotides

Question 5

Ligase function

Answer 5

attaches fragments to the rest of the strand

Question 6

What is the order of events for DNA replication?

Answer 6

1. hydrogen bonds get broken between complementary bases (helicase)
2. RNA primers are added (primase)
3. new nucleotides are added to build DNA strands (DNA poly III)
4. RNA primers are removed and replaced with DNA nucleotides (DNA poly I)
5. fragments of DNA are joined together (Ligase)

Question 7

What are okazaki fragments?

Answer 7

fragments of DNA on the lagging strand

Question 8

leading strand def

Answer 8

the strand which can add nucleotides continuously

Question 9

lagging strand def

Answer 9

the strand which is discontinuous because it doesn’t move towards the replication fork

Question 10

semi-discontinuous

Answer 10

DNA is considered a semi-discontinuous process because the lagging strand is not continuous but the leading strand is

Question 11

True or False:
DNA polymerase III goes after DNA polymerase I

Answer 11

false; it goes before

Question 12

True or False:
the leading strand goes towards the replication fork

Answer 12

true