Brainscape's Knowledge GenomeTM

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


See full index

Biochemistry II > DNA & RNA > Flashcards

DNA & RNA Flashcards

1
Q

This is found in eukaryotic nuclei, prokaryotic cells, mitochondria and chloroplasts

A

DNA

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

Polymer of deoxyribonucleoside mono-phosphates are linked by…

A

3’ to 5’ phosphodiester bonds

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

Which base pairs have only 2 hydrogen bonds?

A

Adenine and Thymine

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

Which base pairs have 3 hydrogen bonds?

A

Cytosine and Guanine

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

What will break hydrogen bonds?

A

Heat or extreme pH

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

This defines the loss of helical structure

A

Denaturation

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

What is DNA synthesis primarily carried out by?

A

DNA polymerases

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

Initiation of DNA synthesis begins where?

A

The replication fork

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

This requires ATP in order to separate the DNA strands during initiation

A

dnaA protein

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

This binds to ssDNA (single-stranded) to keep the DNA strand unwound and uses ATP in the process

A

DNA helicase

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

This protects unwound singles strand DNA

A

SSB (single strand binding protein)

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

These are used to prevent the DNA from “supercoiling” ahead of the replication fork

A

Topoisomerases

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

These enzymes reversibly cut one strand of the double helix. They have both nuclease (strand-cutting) and ligase (strand-resealing) activities. This process stores energy from the phosphodiester bond they cleave, reusing the energy to reseal the strand.

A

Type 1 Topoisomerases

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

These enzymes bind tightly to the DNA double helix and make transient breaks in both strands. The enzyme then causes a second stretch of the DNA double helix to pass through the break and, finally, reseals the
break. This process requires ATP.

A

Type 2 Topoisomerases

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

The DNA polymerases responsible for copying the DNA templates are only able to “read” the parental nucleotide sequences in what direction?

A

3’ to 5’

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

DNA strands are synthesized in what direction

A

5’ to 3’

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

The strand that is being copied in the direction of the advancing replication fork, and that is synthesized continuously is called

A

The leading strand

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

The strand that is being copied in the direction
away from the replication fork that is synthesized discontinuously, with small fragments of DNA being copied near the replication fork is called

A

The lagging strand

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

These short stretches of discontinuous DNA, are eventually joined (ligated) to become a single, continuous strand. The short stretches are known as

A

Okazaki fragments

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

DNA polymerases cannot initiate synthesis of a complementary strand of DNA on a totally single-stranded template. They require…

A

An RNA primer

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

This builds a short double stranded region of RNA with a free 3’ end

A

RNA primase

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

RNA primase triggers the beginning of this

A

DNA synthesis

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

This begins to add nucleotides along the single-stranded template that
specifies the sequence of bases in the newly synthesized chain.

A

DNA polymerase III

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

The processivity of DNA polymerase III is the result of its β subunit forming a ring that encircles and moves along the
template strand of the DNA, thus serving as

A

Sliding DNA clamp

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

The new strand grows antiparallel to the parent strand. It grows in this direction

A

5’ to 3’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

This is released when each new deoxynucleoside monophosphate is added to the growing chain, driving the reaction forward

A

Pyrophosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

All of these must be present for DNA elongation to occur

A

Deoxyribonucleoside triphosphates (dATP, dTTP, dCTP, and dGTP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

This checks to make certain the added

nucleotide is, in fact, correctly matched to its complementary base on the template

A

DNA polymerase III

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

DNA polymerase III continues to synthesize DNA on the lagging strand until it is blocked by proximity to an RNA primer. When this occurs, the RNA is excised and the gap filled by

A

DNA polymerase I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

This can remove one nucleotide at a time from a region of DNA that is properly base-paired. The nucleotides it removes can be either ribonucleotides or deoxyribonucleotides. It also removes groups of altered nucleotides

A

5’ to 3’ exonuclease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

The DNA chain synthesized by DNA polymerase III and the 3’-hydroxyl group on the chain made by DNA polymerase I is catalyzed by

A

DNA ligase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

The joining of these two stretches of

DNA requires energy, which in most organisms is provided by the cleavage of

A

ATP to AMP + PPi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

This is very similar to Prokaryotic DNA replication, has linear chromosomes, and involves 5 different polymerases

A

Eukaryotic DNA replication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

This is a multisubunit enzyme. One subunit has primase activity, which initiates strand synthesis on the leading strand and at the beginning of each Okazaki fragment on the lagging strand.

A

Pol α

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

THIS is thought to be recruited to complete DNA synthesis on the leading strand whereas THIS elongates the Okazaki fragments of the lagging strand, each using 3’ to 5’ exonuclease activity to proofread the newly synthesized DNA.

A

Pol ε; Pol δ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

This is involved in “gap filling” in DNA repair

A

Pol β

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

This replicates mitochondrial DNA.

A

Pol γ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

DNA replication is occurring during this phase of Interphase, prior to mitosis

A

The S (synthesis) phase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

DNA replication in the Cell cycle is regulated closely by

A

Cyclins and cyclin-dependent kinases (cdks)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

These are noncoding DNA sequences that protect ends of linear chromosomes, there activity decreases with age

A

Telomeres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

When a telomere sequence shortens over rounds of replication, this is known as

A

Senescence

42
Q

These may be viewed as mitotic clocks in

that their length in most cells is inversely related to the number of times the cells have divided.

A

Telomeres

43
Q

These are RNA-directed DNA polymerases, used by retroviruses such as HIV to transcribe their DNA elements and randomly insert them into the cell’s genome

A

Reverse transcriptases

44
Q

Sugars that lack a free 3’ end will not be able to participate in replication. This can be known as

A

Inhibition of DNA synthesis

45
Q

Human cells are this, and are broken down into 46 chromosomes in 23 nearly identical pairs

A

Diploid

46
Q

DNA errors can occur during replication, or more likely, through

A

Mutagens

47
Q

This repairs insertions, deletions and mis-incorporation of bases that can arise during DNA replication and recombination.

A

Endonuclease and exonuclease mismatch repair

48
Q

These are DNA repeats which are frequent in DNA tumor suppressor genes.

A

Microsatellites

49
Q

This is an autosomal dominant genetic condition caused by an error in mismatched DNA repair

A

Lynch syndrome

50
Q

This occurs between adjacent pyrimidines; most commonly between T-T dimers

A

Nucleotide excision repair

51
Q

This is a rare, genetic disease where cells cannot repair damaged DNA. Can be susceptible to extreme sunburn, malignant melanoma, and other skin cancers

A

Xeroderma pigmentosum (XP)

52
Q

This is repair of base alterations where bases can slowly or spontaneously change via deamination, or even become lost

A

Base excision repair

53
Q

In base excision repair cytosine turns to this

A

Uracil

54
Q

In base excision repair adenine turns to this

A

Hypoxanithine

55
Q

In base excision repair guanine turns to this

A

Xanithine

56
Q

This removes the single residue in base excision repair

A

Deoxyribose phosphate lyase

57
Q

This is associated with predisposition to cancer and immunodeficiency syndromes, due to ionizing radiation or oxidative free radicals

A

Double-strand break repair

58
Q

This is similar structure to DNA, but single stranded and linear

A

RNA

59
Q

This is the message or direction on how to make a protein

A

mRNA

60
Q

This matches up amino acids(20) with the RNA message, and accounts for only 5% of total RNA in the cell

A

tRNA

61
Q

This is used to bind the mRNA message, and accounts for ~80% of total RNA in the cell

A

rRNA

62
Q

This is a multisubunit enzyme that includes both promoter and termination regions that will control RNA transcription

A

RNA polymerase

63
Q

RNA is synthesized in what direction compared to the DNA template

A

5’ to 3’ antiparallel

64
Q

This begins with RNA pol holoenzyme binding to upstream, non-transcribed region of DNA usually containing consensus sequences

A

Initiation of RNA transcription

65
Q

This is the site of initial DNA unwinding to open transcription bubble in RNA synthesis

A

Pribnow box

66
Q

This step in RNA synthesis uses nucleoside triphosphates as substrates, Lacks 3’ to 5’ exonuclease (proofreading) ability, and processes DNA utilizing sliding clamp mechanism

A

Elongation of RNA Synthesis

67
Q

This type of termination has a hairpin formation

A

ρ-Independent termination

68
Q

This type of termination requires Rho (ρ) protein that uses ATPase activity to release RNA

A

ρ-Dependent termination

69
Q

This prevents bacterial cell growth by inhibiting RNA synthesis via inhibiting binding of RNA polymerase

A

Antibiotics

70
Q

This term describes genes that are tightly coiled in nucleosomes will not be expressed

A

Heterochromatin

71
Q

This type of DNA coiling actively transcribed genes are not condensed

A

Euchromatin

72
Q

This is mediated by histone acetyltransferases (HATs) and histone deactylases (HDACs)

A

DNA coiling

73
Q

This synthesizes precursors of 28S, 18S, and 5.8S rRNA in nucleolus

A

RNA polymerase I

74
Q

This synthesizes precursors of mRNA, some snRNA,

A

RNA polymerase II

75
Q

This serves as binding sites for general transcription factor proteins

A

TATAA box

76
Q

This signals the binding site for the RNA transcription factor

A

CAAT box

77
Q

This binds transcription factors called enhancers

A

GC box

78
Q

Transcription factors bind DNA through

A

Motifs

79
Q

This synthesizes tRNA, 5s rRNA, some snRNA

A

RNA polymerase III

80
Q

This utilizes a single RNA pol more similar to the prokaryotic enzyme

A

Mitochondrial RNA transcription

81
Q

Introns removed from anticodon loop by nucleases is an example of

A

Modifications of tRNA

82
Q

These are non-coding portions of primary RNA transcription

A

Introns

83
Q

These are the coding (expressed) portions of primary RNA transcription

A

Exons

84
Q

This is added by polyadenylate polymerase using ATP in eukaryotic mRNA

A

Poly A tail to 3’ end

85
Q

This helps stabilize mRNA, facilitates exit from the nucleus, and aids in translation in eukaryotic mRNA

A

Poly A tail to 3’ end

86
Q

This protects from nucleases and permits initiation of translation in eukaryotic mRNA

A

5’ capping

87
Q

This removes Introns, at which points Exons are then joined together

A

Splicing

88
Q

This helps to remove introns by forming base pairs with consensus sequences located at the end of introns

A

Mediate splicing

89
Q

This allows for a more diverse set of protein products to be produced from the limited set of genes

A

Alternative splicing

90
Q

In bacteria, one species of RNA polymerase synthesizes all of the RNA except for the short RNA primers needed for DNA replication

A

RNA polymerase

91
Q

This enables RNA polymerase to recognize promoter regions on the DNA.

A

Holoenzyme

92
Q

This enzyme lacks specificity, that is, it cannot recognize the promoter region on the DNA
template

A

Core enzyme

93
Q

This is the initial point of contact for the holo -

enzyme, and a closed complex is formed. It is centered about 35 bases to the left of the transcription start site

A

-35 sequence

94
Q

Chromosomal DNA is thought to consist primarily of what DNA structural form?

A

B-form DNA

95
Q

The conformation found in DNA–RNA hybrids or RNA–RNA double-stranded regions is probably very close to what DNA structural form?

A

A-form DNA

96
Q

Transitions between these two forms of helical

DNA may play a role in regulating gene expression.

A

B & Z form DNA

97
Q

Each chromosome in the nucleus of a eukaryote contains one long, linear molecule of this, which is bound to a complex mixture of
proteins to form chromatin

A

dsDNA

98
Q

The enzymes involved in the DNA

replication process are what?

A

Template-directed polymerases

99
Q

When a new deoxynucleoside monophosphate is added to the growing chain this is a product in replication

A

Pyrophosphate (PPi)

100
Q

This type of Double strand DNA break repair occurs during interphase in replication

A

Homologous Recombination

101
Q

This serves as an “adaptor” molecule that carries its specific amino acid—covalently attached to its 3’-end—to the site of protein synthesis.

A

tRNA

102
Q

In eukaryotic transcription RNA polymerase II has a promoter sequence similar to the prokaryotic

A

Hogness box (TATAAA)

Biochemistry II (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions