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Flashcards in lecture 3 Deck (65)
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1
Q

three theories of replication

A

conservative, semi conservative, dispersive

2
Q

meselson and stahls experiment showed what?

A

semi conservative was true

3
Q

bacteria is what and what? and has how many origins?

A

small and circular. 1

4
Q

types of bacteria replication

A

rolling-circle, theta replication

5
Q

eukaryotic is what and what? with how many origins?

A

large and linear. numerous

6
Q

theta replication unidirectional or bidirectional?

A

both

7
Q

product of theta replication?

A

two circular DNA molecules

8
Q

rolling circle replication unidirectional or bidirectional?

A

unidirectional

9
Q

replication in rolling circle is initiated by what?

A

break in one of the nucleotide strands

10
Q

DNA synthesis begins at what end? and which end is displaced?

A

3’, 5’

11
Q

products of rolling circle?

A

multiple circular DNA molecules

12
Q

what are the products of eukaryotic replication

A

two linear DNA molecules

13
Q

new DNA is synthesized from what?

A

dNTP’s. deoxyribonucleoside triphophate

14
Q

what forms between two necleotides

A

phosphodiester bonds

15
Q

nucleoside=?

A

base and sugar

16
Q

DNA synthesis is mediated by large enzymes called?

A

DNA polymerase

17
Q

DNA polymerase are dependent on what?

A

primers

18
Q

what are primers

A

short strands of DNA or RNA with free 3’ OH groups

19
Q

DNA polymerases do what?

A

add nucleotides one at a time to the free 3’ OH

20
Q

DNA elongation in what direction?

A

5’-3’

21
Q

which strand moves with the replication fork?

A

leading strand

22
Q

which strand moves away from the fork

A

lagging

23
Q

discontinuous strand

A

lagging

24
Q

continuous strand

A

leading

25
Q

okazaki fragments

A

lagging

26
Q

leading requires how many primers?

A

1 at the origin

27
Q

lagging requires how many primers?

A

multiple at beginning of fragment

28
Q

RNA primers have to replaced by what? what does this? then what is need to fill in gap?

A

DNA, polymerase 1. DNA ligase

29
Q

leading and lagging strands are in what two processes?

A

theta replication and eukaryotic replication

30
Q

leading and lagging not in what process?

A

rolling circle

31
Q

four stages of replication

A

initiation, unwinding, elongation, termination

32
Q

what binds to the replication origin?

A

initiator proteins

33
Q

initiator proteins cause what?

A

DNA segment to unwind and form replication bubble

34
Q

helicase does what

A

breaks hydrogen bonds between strands of DNA

35
Q

helicase bind to what?

A

lagging strand template

36
Q

how does helicase move along replication fork?

A

along it in 5’-3’

37
Q

single strand binding proteins do what?

A

stabalize the single stranded DNA during replcation. keeps it from re coiling

38
Q

DNA gyrase is considered a what?

A

topoisomerase

39
Q

DNA gyrase does what?

A

reduces re coiling

40
Q

primase does what

A

syntheses short RNA primer with the 3’ OH group and placed the primer in the orgin

41
Q

elongation or adding of nucleotides requires what?

A

3’ OH group

42
Q

what removes RNA primers and fills in the gap?

A

polymerase 1

43
Q

what is the major replication enzyme?

A

polymerase3

44
Q

which polymerase are involved with DNA repair

A

2,4,5

45
Q

which polymerase have exonuclease in the 3’-5’

A

1,2,3

46
Q

exonucleases:

A

remove a nucleotide only from the end of a chain

47
Q

enconuclease

A

break bonds within a chain

48
Q

enzyme that catalyzes the synthesis of DNA by using template strand

A

polymerase 3

49
Q

enzyme that replaces all RNA primers used to initiate elongation

A

polymerase1

50
Q

what has 5’-3’ exonuclease activity?

A

polymerase 1

51
Q

what fills in the last nick? and how

A

ligae. catalyzes phosphodiester bonds

52
Q

primase add what

A

primer

53
Q

termination can occur in two ways

A

when two forks meet, or TUS which blocks helicase and stalls fork

54
Q

during eukaryotic replication what is needed for initation

A

multi protein recognition complex (ORC)

55
Q

ORC does what

A

initiates unwinding of DNA

56
Q

as replication fork moves away what happens to eh licensing factor?

A

it is removed

57
Q

3 types of polymerase in eukaryotic replication

A

alpha, delta, epsilon

58
Q

which polymerase completes lagging strand?

A

delta

59
Q

which polymerase complete leading strand

A

epsilon

60
Q

alpha polymerase does what

A

initiates both leading and laggin strand . synthesize RNA primer and a short segment of DNA nucleotides (30-40)

61
Q

why can primers at the end of chromosomes not be replaced

A

there is no adjacent 3’OH group that nucleotides can be attatched

62
Q

ends are called what

A

telomere

63
Q

gap is left by what

A

removal of last RNA primer

64
Q

enzyme that aids in the completion of replication?

A

telomerase

65
Q

telomerase is what two things?

A

protein RNA hybrid molecule