chapter 3

Question 1

When the DNA molecule becomes untwisted and the two strands separated, each strand could act as a template for the synthesis of anew complementary strand is known as _______ because each progeny molecule retains one of the parental strands.

Answer 1

semiconservative model

Question 2

When the two parental strands of DNA remain together or part again after replication and, as a whole, serve as a template for the synthesis of a new progeny DNA double helices. One of the two progeny dna molecules is the prental double-stranded dna molecule and the other consists entirely of new material.

Answer 2

conservative model

Question 3

When the parental double helix is cleaved into double-sttranded DNA segments that act as templates for the synthesis of new double-stranded DNA segments. the segments reassemble into complete dna double helices, with parental and progeny dna segments interspersed.

Answer 3

dispersive model

Question 4

In 1958 they obtained experimental evidence that the semiconservative replication model is correct. By growing E. coli in which the only nitrogen source was ammonium chloride. NH4Cl

Answer 4

Matthew Meselson and Frank Stahl

Question 5

In 1955 he was the first to identify the enzymes necessary for DNA replication.

Answer 5

Arthur Kornberg

Question 6

dATP, dGTP, dTTP, dCTP are collectively known as dNTP which stands for

Answer 6

deoxyribonucleoside triphosphate

Question 7

enzymes that catalyze DNA synthesis are called

Answer 7

DNA polymerases.

Question 8

For DNA to be synthesized in vitro 5 components are required.1.______2._______3.________4.________5._________

Answer 8

All four dNTP’S , DNA POL I, E. coli DNA, DNA to act as a primer, and magnesium ions.

Question 9

how many dna polymerases are there?

Answer 9

5 pol I and Pol III are necessary for replication , and Pol I, II, IV, and V are involved in DNA repair.

Question 10

DNA synthesis begins at the ______ prime end of a template strand and moves downward using the DNA polymerase

Answer 10

3

Question 11

how many phosphate groups are removed after a base pair has been assembled?

Answer 11

2

Question 12

the DNA polymerase acts as a ________ when attaching the phosphate groups to each other

Answer 12

catalyst

Question 13

When the DNA polymerase corrects the sequence on a nucleotide it is known as ______ and what is the name of the polymerase?

Answer 13

proofreading, exonuclease

Question 14

The initiation of DNA replication is directed by a sequence called

Answer 14

replicator

Question 15

usually includes the replicator, the specific region where the DNA double helix denatures into single strands and within which replication commences.

Answer 15

origin of replication

Question 16

segments of single strands in the replication bubble on which the new strands are made are called

Answer 16

template strands

Question 17

When DNA untwists to expose the two single stranded template strands for DNA replication , a Y shaped structure is formed called a

Answer 17

replication fork

Question 18

when DNA is being synthesized and the helicase is splitting the double helix the strand that moves in the direction of splitting is called

Answer 18

the leading strand

Question 19

when DNA is being synthesized and the helicase is splitting the double helix the strand that moves in the opposite direction of splitting is called _______ and they form ________ fragments.

Answer 19

the lagging strand. OKAZAKI

Question 20

The process of separation of double-stranded DNA to two single strands is called DNA ________ or DNA______

Answer 20

denaturation, melting

Question 21

SSB what is it?

Answer 21

Single-strand DNA-binding proteins bind to each single stranded dna stabilizing them

Question 22

Each RNA primer is extended by the addition of DNA nucleotides by which polymerase?

Answer 22

Pol III

Question 23

Because the leading strand is synthesized continuously, whereas the lagging strand is synthesized in pieces, discontinuously, DNA replication as a whole occurs in a ________

Answer 23

semidiscontinuous manner

Question 24

what joins two Okazaki fragments together when DNA replication is done?

Answer 24

Pol I, and DNA ligase