Replication of DNA

Question 1

4 things that must be present for DNA replication

Answer 1

Enzymes
Primers
DNA nucleotides
Template strand

Question 2

What is a primer

Answer 2

Short strand of DNA nucleotides that binds to 3’ end of DNA template strand

Question 3

Role of a primer

Answer 3

Allows a start point for DNA polymerase to begin replication of DNA

Question 4

Name the 2 enzymes involved in DNA replication

Answer 4

DNA polymerase

Ligase

Question 5

Role of DNA polymerase

Answer 5

Adds complementary nucleotides to the 3’end of the new strand that is forming

Question 6

Role of ligase

Answer 6

Joins fragments of DNA together on lagging strand

Question 7

Type of replication of lagging strand

Answer 7

Discontinuous

Question 8

Type of replication on leading strand

Answer 8

Continuous

Question 9

Why is lagging strand replicated in fragments

Answer 9

DNA polymerase can only add DNA nucleotides in one direction from 3’ to 5’ end

Question 10

Purpose of PCR

Answer 10

To amplify DNA

Question 11

What is PCR

Answer 11

repeated cycles of heating and cooling to amplify target region of DNA

Question 12

What happens in stage 1 of PCR

Answer 12

DNA heated to between 92 and 98 degrees to separate strands by breaking hydrogen bonds between bases

Question 13

What happens in stage 2 of PCR

Answer 13

DNA cooled to between 50 and 65 degrees to allow primers to bind to target sequences

Question 14

What happens in stage 3 of PCR

Answer 14

DNA heated to between 70 and 80 degrees for heat tolerant DNA polymerase to replicate the region of DNA.

Question 15

What is PCR used for

Answer 15

Solving crimes

Setting paternity suits