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Flashcards in DNA replication: Repair Deck (15)
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1

A large protein complex forms at the origin of replication. One of the these initiator proteins is the product of what gene?

adnA gene

2

How many replication units are present in genomes?

20-80

3

What is an ARS?

Autonomous Replicating Sequence. Contains all elements necessary for replication. It includes the sequence required to bind the origin recognition complex

4

What is the ORC?

Origin recognition complex. Binds to chromosome most of the cell cycle

5

After the telomerase adds extra nucleotides to the end of the strand, what polymerase synthesizes the strand?

alpha

6

Define Depurination

Cleavage of the bond between the purines and the sugar

7

Define deamination

Loss of an amine turns a cytosine into uracil

8

What is thymine dimers?

A mutation where two adjacent thymines stick together. Caused by the sun

9

what enzyme excises misplaced base

specific base glycosylase

10

What excises the sugar-phosphate backbone of a misplaced nucleotides

endonuclease and phosphodiesterase

11

Define base excision repair

One misplaced nucleotide is excised and replaced by DNA polymerase, followed by ligation

12

Define nonhomologous end joining

When dsDNA is broken, its joined back together, with the loss of several nucleotides

13

Define homologous recombination

Use of sister chromatid as template to repair missing section caused by break

14

What is the importance of the H2AX histone variant

Is able to quickly spread across DNA after a break has occurred, attracting repair machinery and slowing transcription of genes.

15

What are the two types of double stranded break repair?

non-homologous end joining and homologous recombination