Dna Replication

Question 1

DNA replication enzymes

Answer 1

Helicase, primase, single strand binding protein, DNA polymerase 111, DNA polymerase I, ligase, topoisomerase

Question 2

primase function

Answer 2

Builds RNA primer onto origin of replication for leading strand and at various points behind it for Okazaki fragments. Each primer is approx 10 nucleotides and has a reactive OH group on the 3’ end

Question 3

Helicase function

Answer 3

Binds to ta-rich region and unwinds strands to form a replication bubble

Question 4

Single strand binding proteins function

Answer 4

Binds to single strands, prevents degradation and the strands from rejoining

Question 5

DNA polymerase III

Answer 5

Builds DNA nucleotides onto RNA primer and double checks nucleotides (and fixes mistakes)

Question 6

DNA polymerase I function

Answer 6

Rnase H function degrades RNA primer, polymerase function replaces those nucleotides with DNA

Question 7

DNA ligase function

Answer 7

Joins together DNA strands with phosphodiester bonds

Question 8

Repairing mistakes during replication

Answer 8

Exonuclease - DNA polymerase III fixes from ends of DNA strands

Question 9

Repairing mistakes after replication

Answer 9

Endonuclease destroys section of DNA and DNA polymerase rebuilds it