1.2 - Replication of DNA

Question 1

when does replication of DNA take place?

Answer 1

prior to cell division

Question 2

what enzyme replicates dna?

Answer 2

dna polymerase

Question 3

what is needed to start replication

Answer 3

a primer

Question 4

what is a primer?

Answer 4

a short strand of nucleotides

Question 5

where does a primer bind?

Answer 5

the 3’ end of the template strand

Question 6

what does a primer allow?

Answer 6

dna polymerase to add dna nucleotides

Question 7

what method does dna polymerase use to add dna nucleotides to the 3’ end of the new strand?

Answer 7

complimentary base pairing

Question 8

what is done to the original piece of dna before it is able to be copied and what does it form?

Answer 8

it is unwound and the hydrogen bonds between bases are broken forming 2 template strands

Question 9

the leading strand is replicated ………

Answer 9

continuously

Question 10

the lagging strand is replicated in ……..

Answer 10

fragments

Question 11

what characteristic of dna polymerase means it can only add nucleotides in one direction?

Answer 11

it can only add nucleotides to the 3’ end of the deoxyribose sugar

Question 12

how are the fragments of the lagging strand joined together

Answer 12

using ligase

Question 13

in pcr, primers are short strands of nucleotides which…

Answer 13

are complementary to specific target sequences at the 2 ends of the region of dna to be amplified

Question 14

what are the 3 temperatures of pcr stages

Answer 14

93, 63, 73

Question 15

dna is heated to 93 to …………………

Answer 15

separate the strands

Question 16

dna is cooled to 63 to……………

Answer 16

allow primers to bind to their target sequences

Question 17

dna is heated to 73 for …………………..

Answer 17

heat tolerant dna polymerase to replicate the region of dna

Question 18

pcr is used to do what to dna?

Answer 18

amplify it

Question 19

what are the practical uses of pcr

Answer 19

solving crime, settle paternity suits, diagnose genetic disorders