Lec 3-2

Question 1

Eukaryotic DNA replication

Initiation and Unwinding

Origin-recognition complex (ORC)

Answer 1

Loads helicase onto dsDNA

Question 2

Eukaryotic DNA replication

Helicase is activated during

Answer 2

S phase

Question 3

DNA polymerase alpha

Answer 3

DNA synthesis on the lagging strand

Question 4

DNA polymerase delta

Answer 4

DNA synthesis on the leading strand

Question 5

Okazaki fragments filled in by

Answer 5

DNA polymerase alpha

Question 6

DNA ligase

Answer 6

Stiches Okazaki fragments together

Question 7

Termination

Answer 7

Termination happens due to two forks running into each other

Question 8

How to quickly replicate a large genome

Answer 8

Eukaryotic genomes contain multiple origins of replication

Question 9

Multiple origins of replication

Replicon

Answer 9

Unit of replication consisting of DNA independently replicated starting from one origin of replication

Question 10

Nucleosome

Answer 10

The fundamental unit of chromatin (2 turns of DNA around a histone octamer)

Question 11

Nucleosomes rapidly disassemble and reassemble

Steps

Answer 11

Replication for disruption of original nucleosomes on the parental DNA

Redistribution of preexisting histones on the new DNA

The addition of newly synthesized histones to complete the formation of new nucleosomes

Question 12

Replication licensing factors

Answer 12

Bind to origins

ORC attaches to origins and two licensing factors recruits MCM2-7

Question 13

Telomeres

Answer 13

Repeating sequences at the end of DNA

Question 14

Telomerase

Answer 14

Ribonucleoprotein. Enzyme that elongates the end of eukaryotic chromosomes.

Reverse transcriptase (RNA–>DNA)

Has specialized reverse transcriptase activity

G-rich 3’ overhang extended by Telomerase