Ch.6 & 7

Question 1

what two things add variation to a species

Answer 1

recombination (sexual reproduction) and mutations

Question 2

error rate for DNA replication

Answer 2

1 in 10^7

Question 3

DNA replication requires:

Question 4

DNA replication is ____

Answer 4

semiconservative

Question 5

The result of semiconservative DNA replication is (heavy and light DNA strands turns into; one light, one intermediate)

Answer 5

one old and one new strand

Question 6

how many replication origins exist in human genome

Answer 6

10,000

Question 7

replication origins are A-T or G-C rich

Answer 7

A-T

Question 8

replication forks move in the same direction or bidirectional

Answer 8

bidirectional

Question 9

enzyme that polymerizes DNA during replication is

Answer 9

DNA polymerase

Question 10

DNA polymerase requires what three things to begin replication

Answer 10

template, nucleotides (atgc) and 3-OH on growing end

Question 11

direction of chain growth is

Answer 11

5’-3’

Question 12

DNA polymerase has proofreading ability, true or false?

Answer 12

true

Question 13

_____ primers are added to the lagging strand and are later removed and replaced with DNA

Answer 13

RNA

Question 14

RNA primer is removed from okazaki fragment by a _____ and replaced by a DNA sequence then joined together by ____ _____

Answer 14

nuclease, DNA ligase

Question 15

what unwinds the DNA for the replication form

Answer 15

helicase

Question 16

Topoisomerase function is to

Answer 16

release tension caused by helicase

Question 17

sickle cell is caused by a

Answer 17

SNP

Question 18

xeroderma is caused by errors in

Answer 18

nucleotide excision repair

Question 19

purines have how many rings in their structure

Answer 19

2

Question 20

depurination is a loss of _____ bases

Answer 20

purine (A and G)

Question 21

removal of a _____ in DNA is common, it is hydrolyzed producing uracil in its place

Answer 21

cytosine

Question 22

thymine dimers are promoted by

Answer 22

UV radiation

Question 23

damaged DNA is recognized and cleaved by ______

Answer 23

nucleases

Question 24

mismatch repair is used for rare errors in DNA replication, typically used for _____ nucleotides

Answer 24

single

Question 25

all homologous endjoining uses ______ junction

Answer 25

holliday

Question 26

repairs broken chromosomes; produces indels; loss of nucleotides at repair site

Answer 26

non homologous end joining

Question 27

very accurate reponse to double stranded break; occurs soon after DNA replication; identical sequences in homologous chromosome is used as a template

Answer 27

homologous recombination

Question 28

DNA polymerase extends the strand using the template of the homologous chromosome (Accurate)

Answer 28

double stranded break repair