DNA Polymerase MCDB 108A

Question 1

DNA replication is _______ and requires the strands of double helix to be separated before being copied

Answer 1

semi conservative

Question 2

dna synthesis proceeds in a ____ direction

Answer 2

5-3

Question 3

DNA polymerases require a ______ and a _____ and metal ion _____

Answer 3

template, primer, cofactor

Question 4

meselson stahl experiement determined _______ nature of DNA

Answer 4

semiconservative

Question 5

______ replication is when one daughter DNA molecule is all new and the other is all old

Answer 5

conservative

Question 6

______ replication is when each daughter DNA molecule contains a mixture of old and new DNA

Answer 6

dispersive

Question 7

_____ replication is when each daughter DNA molecule contains one new strand and one old strand

Answer 7

semiconservative

Question 8

biochem approach to discover DNA polymerase
- incorporate radioactive nucleotides into large polymer
-fractionation to purify ____
-reconstitution showing dna was needed as ____ because radioactive nucleic acids had same comp as provided template DNA

Answer 8

enzyme, template

Question 9

cells contain different ____ _______

Answer 9

DNA polymerases

Question 10

DNA synthesis is _______, _______ addition of dNTP’s to a growing DNA chain.

Answer 10

stepwise, directional

Question 11

DNA polymerases share common ________ features. they have _____ ______ _____

Answer 11

structural, fingers, palm, thumb

Question 12

DNA polymerases require metal ion _____

Answer 12

cofactors

Question 13

DNA polymerization entails a ______ attack of the 3’OH of the growing chain on the inner most phosphate of _____

Answer 13

nucleophilic, dNTP

Question 14

the template strand determines the correct incoming _____ to add

Answer 14

nucleotide

Question 15

after addition of nucleotide to templeate strand the ________ advances

Answer 15

polymerase

Question 16

DNA polymerases make ___ errors

Answer 16

few

Question 17

mechanism for high fidelity of DNA polymerases are
_____ pairing
____ complementarity in the active site
proofreading
repair of ____ by other surveillance enzymes

Answer 17

base, shape, mismatches

Question 18

there are ________ changes in DNA polymerase upon nucleotide binding

Answer 18

conformational

Question 19

______ do not fit well on the active site of DNA polymerase and largely are excluded

Answer 19

mismatches

Question 20

polymerases can ____ to correct mistakes -proofreading, by slowing movement to give more time for molecule

Answer 20

backtrack

Question 21

cells invest alot of ____ to maintain _____. there are many DNA ____ mechanism to fix different types of lesion.

Answer 21

energy, genome, repair

Question 22

failure to maintain ______ integrity leads to disease

Answer 22

genome