DNA replication

Question 1

when does DNA replication occur in the cell cycle ?

Answer 1

it occurs before mitosis, in the S- phase

Question 2

why does DNA replication occur before mitosis ?

Answer 2

because before the cell divides all the DNA must replicate to provide a copy for the new cell

Question 3

the process of DNA replication is described as… ?

Answer 3

semi-conservative method

Question 4

why is DNA replication described as semi-conservative ?

Answer 4

because in the daughter DNA , one strand is from the original, parental DNA and one strand is newly synthesised

Question 5

which enzymes are involved in DNA replication ?

Answer 5

DNA helicase
DNA polymerase

Question 6

step 1 of DNA replication

Answer 6

DNA helicase breaks the hydrogen bonds between the complementary base pairs between the 2 strands whithin a double helix
this causes the DNA double helix to unwind

Question 7

what is meant by parental DNA ?

Answer 7

name given to the original DNA that is gong to be copied

Question 8

step 2 of DNA replication

Answer 8

each of the separated parental DNA strands acts as a template
free floating DNA nucleotides within the nucleus are attracted to their complementary base pairs on the template strands of the parental DNA

Question 9

step 3 of DNA replication

Answer 9

the adjacent nucleotides are joined to form the phosphodiester bond by a condensation reaction
- DNA polymerase catalyses the joining together of adjacent nucleotides

Question 10

step 4 of DNA replication

Answer 10

the 2 sets of daughter DNA contains one strand from the parental DNA and one newly synthesised strand