Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

genetics > Chapter 7 > Flashcards

Chapter 7 Flashcards

1
Q

what is the central dogma of molecular biology

A

replication (DNA) -> transcription (RNA) -> translation (protein)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

DNA nucleotides contain (3)

A

1) sugar (deoxyribose)
2) one of the 4 nitrogenous bases
3) 1-3 phosphate groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

a deoxyribose has _____ carbons? and what is connected to each carbon

A

5
OH at the 3’
only H at the 2’
nucleotide base at the 1’
1-3 phosphates at the 5’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are the 2 classes of DNA nucleotides and how do you differentiate the 4 bases?

A

1) purines (double ring, AG) and pyrimidines (single ring, TC)
2) G is more decorated than A and T has more O’s than C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Deoxynucleotide triphosphates act as substrates for _______. How many phosphates are used?

A

DNA synthesis
2 phosphates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

deoxynucleotide monophosphates are apart of _______

A

polynucleotide chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

individual nucleotides are assembled into chains by the enzyme _______

A

DNA Polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

DNA polymerase catalyzed the formation of a _______ between the 3’ _______ and the 5’ ______ of 2 nucleotides

A

1) phosphodiester bond
2) OH
3) phosphate group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

each polynucleotide chain has an alternating _______ backbone

A

sugar-phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The bases of one strand are complementary to the bases in the corresponding strand. which bases pair with which bases?

A

A with T and G with C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

the two strands are _______ with respect to their 5’ and 3’ ends

A

antiparallel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what happens if the 2 strands of DNA are parallel

A

the charges on the complementary nucleotides would repel each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

complementary base pairing pairs one _______ with one _______ (classes of nucleotides)

A

purine with one pyrimidine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

1) G - C forms how many_____ bonds?
2) A - T forms how many _____ bonds?
Which uses less energy (heat) to make or break bonds

A

1) 3 H-bonds
2) 2 H bonds
AT uses less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What causes grooves in the DNA to form?

A

base pair stacking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

The _______ approximately 12 A wide, alternates with the _______ approximately 6 A wide

A

major groove
minor groove

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The major and minor grooves are regions where _______ proteins can make direct contact with nucleotides

A

DNA binding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

explain B form DNA

A

most common
10.5 bases per turn
bases are perpendicular to long axis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

explain A form DNA

A

11 bases per turn
bases are not perpendicular to long axis
found in dehydrating conditions (crystallization)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

explain Z form DNA

A

left-handed helix, zig-zag apperance
12 bases per turn
found at the beginning of gene transcription

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

DNA replication is usually _______ proceeding in both directions
bacterial circular chromosomes have _______ origin of replication while Eukaryotic linear chromosomes have _______ origins of replication

A

bidirectional
single
multiple

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

large eukaryotic genomes contain _______ origins of replication seperated by _______ base pairs

A

thousands
40k-50k

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The human genome contains more than _______ origins

A

10k

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

the enzymes and proteins involved in DNA replication are parts of a large complex aggregations of proteins and enzymes called the _______

A

replisome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

the origin of replication sequence of E.coli is called _______

A

ori-c

26
Q

Ori-c contains about _______bp of AT rich DNA and is devided into _______bp sequences followed by _______ bp sequences

A

245
(3) 13
(4) 9

27
Q

explain initiation of replication (3)

A

1) DnaA binds to the 9 mer sequence and bends the DNA
2) Dna B carried by DnaC
3) Dna B is a helicase and uses atp energy

28
Q

The unwound DNA strands are kept from reannealing by _______

A

Single stranded binding protein (SSB)

29
Q

enzymes called _______ catalyze controlled cleavage and rejoining of DNA that prevents over winding and relieves torsional stress

A

topoisomerase

30
Q

What kind of bond does topoisomerase break?

A

covalent bond

31
Q

Saccharomyces Cerevisiae (_______) has the most fully characterize origin of replication sequences which are called _______

A

yeast
autonomous replicating sequences (ARS)

32
Q

RNA primers are needed in replication and are synthesized by a RNA polymerase called _______

A

primase

33
Q

In E.coli, daughter DNA strands are synthesized by the _______

A

DNA Polymerase III holoenzyme

34
Q

what is bigger, the replisome or the holoenzyme

A

replisome

35
Q

One copy of pol III synthesizes a daughter strand continuously in the same direction as the replication fork; this strand is called the _______?

A

leading strand

36
Q

This daughter strand is synthesized discontinuously in the opposing direction of the fork and is called the _______? it is composed of segments called _______?

A

lagging strand
Okazaki fragments

37
Q

DNA polymerase has 2 activities to complete replication, what are they?

A

1) 5’->3’ exonuclease activity
2) 5’->3’ polymerase activity

38
Q

_______ seals the gap between the resulting DNA segments by catalyzing the formation of new phosphodiester bonds between neighboring nucleotides

A

DNA Ligase

39
Q

The DNA pol III holoenzyme is made up of what

A

1) 2 polymerase III core enzymes
2) tau proteins
3) clamp loader
4) sliding clamp (made from 2 proteins)

40
Q

What does DNA polymerase have that allows it to proofread? what are the 2 active sites

A

3’->5’ exonuclease activity
polymerase active site
exonuclease active site

41
Q

The problem with DNA replication because the lagging strand can’t be completely replicated is resolved by what repetitive sequence at the end of chromosomes?

A

telomeres

42
Q

telomere sequences are synthesized by the ribonucleoprotein _______

A

telomerase

43
Q

How does telomerase extend DNA? (4)

A

1) telomerase binds to DNA using its own RNA template
2) it extends the parental strand a couple of times
3) alpha polymerase binds and synthesizes RNA primers
4) DNA polymerase fills in the missing strand

44
Q

Most eukaryotic telomeres contain a DNA sequence that forms a knotted fold called the _______

A

T-loop

45
Q

the T loop binds the _______ protein complex which protects the telomeres from degradation, but telomere shortening will eventually trigger _______

A

shelterin
apoptosis

46
Q

the _______ represents the number of cell cycles of a vertebrate cell before the cell succumbs to apoptosis

A

Hayflick limit

47
Q

Telomerase _______ is associated with normal aging of cells

A

inactivity

48
Q

_______ causes early onset of some features of aging and is the result of a mutation in the RECQL2 gene encoding a _______ for telomerase activity

A

Werner syndrome
helicase

49
Q

_______ is a disorder associated with the loss of a function of a gene DKC1

A

dyskeratosis congenita

50
Q

telomerase is usually turned ____ in somatic cells but _______ reactivation is a common mutation in cancers

A

off
TERT

51
Q

What is TERT resposible for in telomerase

A

encoding the reverse transcriptase function

52
Q

The _______ is an automated version of DNA replication

A

PCR

53
Q

PCR requires:
- double-stranded _______
- supply of the 4 _______
- heat stable _______
- 2 different single stranded DNA _______
- a _______ solution

A

1) DNA template
2) nucleotides
3) taq polymerase
4) primers
5) buffer

54
Q

what are the 3 steps to PCR and at what temperature do they occur at?

A

1) denaturation (95°C)
2) primer annealing ( 45°C-68°C)
3) primer extension (72°C)

55
Q

What is special about the dye used in realtime PCR or qPCR

A

SYBR green is only florescent when bound to DNA

56
Q

What are the benefits of ddPCR (3)

A

1) highly quantitative
2) very sensitive
3) very precise

57
Q

Describe sanger sequencing

A

dideoxynucleotide DNA sequencing that uses small amounts of ddntp’s that lack a 3’ OH that will kill the sequence. A bunch of fragments are found and then incorperated together to sequence DNA

58
Q

Describe Griffith’s experiment and how Avery, McCarty, and MacLeod expanded on it

A

Griffith found a transforming factor between S and r strain bacteria and MMA found that the genetic material for the bacteria was DNA

59
Q

Describe Hershey and Chase’s experiment

A

Waring blender (radioactive P32 for DNA and S35 for protein)

60
Q

describe Meselson and Stahl’s experiment

A

conservative, semiconservative, and dispersive using DNA grown in N14 and N15

genetics (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions