Ch. 12 DNA Replication and Recombination

Question 1

Replication results in a random mix of old and new DNA in two daughter DNA’s

Answer 1

dispersive

Question 2

Replication results in one completely new DNA and one completely old DNA

Answer 2

conservative

Question 3

Replication results in two DNA molecules where each molecule has one old and one new strand

Answer 3

semiconservative

Question 4

How does DNA replicate?

Answer 4

semiconservative

Question 5

The location where DNA begins

Answer 5

origin of replication

Question 6

Has one replication bubble?

Answer 6

theta

Question 7

Has many replication bubbles?

Answer 7

linear

Question 8

Used for circular chromosomes?

Answer 8

theta

Question 9

Is linear replication unidirectional or bidirectional?

Answer 9

bidirectional

Question 10

True or False: Eukaryotes use linear DNA replication

Answer 10

True

Question 11

What are the requirements of replication?

Answer 11

single-strand DNA template
dNTP’s
enzymes

Question 12

To which end of DNA is the new nucleotide added?

Answer 12

3’

Question 13

What group at the 3’ is the most important?

Answer 13

OH

Question 14

DNA is…

Answer 14

antiparallel
complementary
made from 5’ to 3’

Question 15

What bond is in the backbone of DNA?

Answer 15

phosphodiester

Question 16

Which direction is the template strand read?

Answer 16

3’ to 5’

Question 17

Which direction is the new strand being made?

Answer 17

5’ to 3’

Question 18

leading strand=

Answer 18

continuous

Question 19

lagging strand=

Answer 19

discontinuous

Question 20

If the new strand goes 5’ to 3’ into the fork…

Answer 20

leading

Question 21

If the new strand goes 5’ to 3’ away from the fork…

Answer 21

lagging

Question 22

What small fragments are formed on the lagging strand?

Answer 22

Okazaki

Question 23

What enzyme adds new nucleotides to the DNA strand?

Answer 23

DNA polymerase

Question 24

What enzyme fuses the Okazaki fragments?

Answer 24

ligase

Question 25

What enzyme relieves strain?

Answer 25

topoisomerase/gyrase

Question 26

What enzyme unwinds the DNA?

Answer 26

helicase

Question 27

What is the order of bacteria replication?

Answer 27

initiation unwinding elongation termination

Question 28

What binds to the DNA to prevent the DNA from forming hairpins?

Answer 28

single-strand binding proteins

Question 29

True or False: In bacteria, DNA polymerase starts the synthesis of the new strand

Answer 29

False

Question 30

In bacteria, what starts the synthesis of the new strand?

Answer 30

primase with RNA primer

Question 31

What is primase?

Answer 31

RNA polymerase

Question 32

Why is a primer required?

Answer 32

adds a 3' OH

Question 33

What does exonuclease activity mean?

Answer 33

removing nucleotides

Question 34

What does polymerase activity mean?

Answer 34

adding nucleotides

Question 35

5' to 3' polymerase activity...

Answer 35

DNA polymerase I DNA polymerase III

Question 36

3' to 5' exonuclease activity

Answer 36

DNA polymerase I DNA polymerase III

Question 37

5' to 3' exonuclease activity

Answer 37

DNA polymerase I

Question 38

Main function is DNA repair

Answer 38

DNA polymerase II DNA polymerase IV DNA polymerase V

Question 39

What is the main function of DNA polymerase I?

Answer 39

replacing RNA primer

Question 40

What is the main function of DNA polymerase III?

Answer 40

elongation

Question 41

What enzyme connects the replaces primer to new strand?

Answer 41

ligase

Question 42

Which of the following are examples of DNA replication being high accurate?

Answer 42

nucleotide selection proofreading mismatch

Question 43

DNA polymerase alpha

Answer 43

primase activity

Question 44

DNA polymerase delta

Answer 44

lagging strand synthesis

Question 45

DNA polymerase epsilon

Answer 45

leading strand synthesis

Question 46

True or False: circular chromosomes have telomeres

Answer 46

False

Question 47

In linear chromosomes, DNA replication leaves gapes at the end of a chromosome, causing shortening over time

Answer 47

the end replication problem

Question 48

True or False: telomerase solves the end replication in all eukaryotic cells

Answer 48

False

Question 49

What cells does telomerase operate in?

Answer 49

germ cells (gametes) bone marrow cells

Question 50

What template is used in extending telomeres?

Answer 50

RNA template

Question 51

Which strand of the DNA does telomerase extend?

Answer 51

G rich

Question 52

Identify what would happen if the following mutation occured: single-strand binding proteins are degraded

Answer 52

hairpins

Question 53

Identify what would happen if the following mutation occured: helicase is deactivated

Answer 53

replication

Question 54

Identify what would happen if the following mutation occured: topoisomerase/gyrase is functioning slower than usual

Answer 54

DNA would replicate more slowly

Question 55

A woman goes to the doctor for her annual checkup. After noticing some concerning signs, the doctor decides to do a DNA analysis of many different cells. DNA is extracted from her skin, liver, and stomach tissue. The DNA is then analyzed. The results found that every DNA molecule was different lengths, and they all ended in a guanine nucleotide. In addition one strand was usually longer than the other. What could explain these results?

Answer 55

G nucleotides are missing 3' OH

Question 56

A student works in a lab and is analyzing DNA samples from mice. He notices that there are locations in the DNA that do not have phosphodiester bonds. What could explain these results?

Answer 56

Okazaki fragments not fused

Question 57

Describe the effect of the following mutations: helicase stops working halfway through replication

Answer 57

replication bubble cannot continue

Question 58

Describe the effect of the following mutations: primase is not functional

Answer 58

there will only be on the DNA

Question 59

Describe the effect of the following mutations: DNA polymerase III is degraded

Answer 59

only primers will be on the DNA

Question 60

Describe the effect of the following mutations: DNA polymerase I can no longer bind to DNA

Answer 60

there will be a mix of DNA and RNA

Question 61

Describe the effect of the following mutations: DNA polymerase delta is working extremely fast

Answer 61

lagging strand os being formed quickly