Enzymes

Question 1

DNA Gyrase

Answer 1

relaxes supercooling ahead of the replication fork

Question 2

DNA ligase

Answer 2

makes covalent bonds to join DNA strands; Okazaki fragments, and new segments in excision repair

Question 3

DNA polymerase

Answer 3

synthesize DNA; proofread and facilitate repair of DNA

Question 4

endonucleases

Answer 4

cut DNA backbone in a strand of DNA; facilitate repair and insertions

Question 5

exonucelases

Answer 5

cut DNA from an exposed end of DNA; facilitate repair

Question 6

helicase

Answer 6

unwinds double stranded DNA

Question 7

methylase

Answer 7

adds methyl group to selected bases in newly made DNA

Question 8

photolyase

Answer 8

uses visible light energy to separate UV-induced pyrimidine dimers

Question 9

primase

Answer 9

an RNA polymerase that makes RNA primers from a DNA template

Question 10

Ribozyme

Answer 10

RNA enzyme that removes introns and splices exons together

Question 11

RNA polymerase

Answer 11

copies RNA from a DNA template

Question 12

snRNP

Answer 12

RNA protein complex that removes introns and splices exons together

Question 13

Topoisomerase/Gyrase

Answer 13

relaxes supercooling ahead of replication fork; separates DNA circle at the end of DNA replication

Question 14

Transporase

Answer 14

Cuts DNA backbone, leading single stranded ‘sticky ends’