Brainscape's Knowledge GenomeTM

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


See full index

genetics > Exam 2 > Flashcards

Exam 2 Flashcards

Ch.6-12

1
Q

Transcription is

A

DNA to RNA

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

ribosomal RNA (rRNA)

A

-structural and functional components

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

messenger RNA (mRNA)

A

carries genetic code for proteins

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

transfer RNA (tRNA)

A

helps incorporate amino acids into polypeptide chain

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

requirements for transcription

A

template, substrate, transcription complex or RNA polymerase and factors

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

the top strand is also called the

A

sense, non-template, and coding

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

the bottom strand is also called the

A

Template, noncoding, and antisense

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

transcription unit and main features

A

-stretch of DNA that encodes a RNA molecule
-promoter, coding region, and terminator

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

transcription unit: promoter

A

-most upstream
-recognizes gene that needs to be transcribed

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

transcription unit: coding region

A

-in the middle
-largest area of the strand
-actually used for the new RNA
-5 to 3 end

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

transcription unit: terminator

A

-smallest section of strand
-most downstream

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

gene organization differs between

A

prokaryotes and eukaryotes

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

prokaryotic gene organization (2 types)

A

single gene: codes for 1 protein
operon: codes for 4 proteins, acts like a lagging strand

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

eukaryotic gene organization

A

-introns and exons

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

prokaryotic mRNA is processed or not processed?

A

not processed

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

eukaryotic mRNA is processed or not processed?

A

processed

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

Prokaryotic mRNA

A

-recognized by ribosomes
-has the Shine Dalgarno sequence
-the untranslated regions are not translated into proteins but are synthesized

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

Shine Dalgarno sequence

A

-only in prokaryotes
-recognizes small subunit of ribosome and positions at A site so AUG is translated first

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

eukaryotic mRNA

A

-has the kozak sequence
-has poly(A) tail
-the untranslated regions are not translated into proteins but are synthesized
-Kozak sequence surrounds AUG

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

kozak sequence

A

-only in eukaryotes
-embeds the start and shows ribosome where to put amino acids

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

untranslated regions are there so…

A

-the sequence is recognizable by proteins

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

transcription unit: differences in the organization of prokaryotes and eukaryotes

A

-eukaryotic are present as one gene per transcription unit
-eukaryotes have coding regions (exons) and noncoding regions (introns) which are removed by splicing

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

exons

A

-Eukaryotic transcription unit
-coding regions

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

introns

A

-eukaryotic transcription unit
-not coding
-removed by splicing

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

eukaryotic transcription unit (__->)

A

DNA-> premature mRNA -> mature mRNA (monocistronic)-> protein

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

the 3 types of mRNA processing

A

-covalent modifications (modified m7G (methyl) caps or addition of poly-A tail)
-cleavage/ trimming to generate ends (addition of poly (A) tail)
-splicing (intron removal, joins exons, pre to mature mRNA)

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

consensus sequence

A

-sequences of 4 diff bacterial DNA regions
-compares for common features or “consensus”
-consensus: short stretches of common nucleotides

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

introns are

A

removed

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

Translation

A

RNA to protein

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

rRNA

A

-actually apart of the ribosome
-has a large and small subunit (large is on top)

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

prokaryotic transcription unit

A

-genes are together in an operon, also called polycistronic
-genes expressed together
-every 3 bases there is a codon
-shine sequence is before the AUG start

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

prokaryotic transcription unit (->)

A

-DNA -> RNA-> proteins (multiple)

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

amino acids are encoded in

A

the bases

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

there are __ common amino acids

A

20

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

structure of amino acids

A

-carbon center
-top 3 stay the same (L: amino group, T: H, R: carboxyl group)
-bottom changes

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

all amino acids are joined by a

A

peptide bond which is always between the carboxyl and amino end

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

the genetic code is read in

A

triplet
-each triplet encodes a single amino acid

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

base pairing and wobble of the 3rd position

A

-when tRNAs attach to the codons the fist and second bases are strict
-the third has the ability to base pair with alternate bases (so its called the wobble base)

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

during translation the mRNA code is “read” by the ribosome to build a __

A

polypeptide chain

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

entrance site

A

tRNA binds to the A site on the ribosome

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

exit site

A

E tRNA

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

each tRNA is charged with a specific __

A

amino acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

ribosomes have 3 sites within

A

E, P, A
E site: exit site, empty tRNA leaves ribosome
P site: peptide chain
A site: holds tRNA carrying the next amino acid to be added to the chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

initiation of translation: eukaryotes

A

-2 cap binding proteins sit around the ribosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

how the flow of information is regulated

A

-genes are not always expressed at all times
-only expressed when needed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

regulatory element is another name for

A

promoter, and operator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

genes that are always expressed are called

A

housekeeping genes

47
Q

structural genes

A

encodes proteins

48
Q

regulated

A

not always expressed

49
Q

constitutive

A

always expressed

50
Q

regulatory genes

A

-encode RNA or proteins that interact with other DNA sequences

51
Q

regulatory elements

A

-not transcribed, affect expression of DNA
-also known as promoter

52
Q

negative control

A

-regulation inhibits gene expression
-regulator protein is a repressor

53
Q

positive control

A

-regulation stimulates gene expression
-regulator protein is an activator

54
Q

operon regulation: the operator

A

-DNA sequence situated upstream of the genes and downstream of the promoter or regulatory element
-recognized by regulator proteins and determines where transcription will take place
-the operator and promoter overlap

55
Q

the regulatory protein binds to …

A

the operator

56
Q

regulatory protein types

A

-repressor
-activator

57
Q

(- operons) - inducible

A

off-> on

58
Q

(- operons) - repressible

A

on-> off

59
Q

(+ operons) + inducible

A

on-> off

60
Q

gene regulation is how often …

A

a gene is transcribed

61
Q

eukaryotes have histones which get in the way so they must…

A

be moved or removed
-often slid along the DNA

62
Q

chromatin

A

DNA complex making up the chromosomes

63
Q

nucleosomes

A

-core unit of chromatin

64
Q

histones

A

-primary protein of chromatin

65
Q

histones have 2 domains

A

-globular domain: associates with other histones and DNA
-tail: (+) charged tail which interacts with the (-) charged DNA backbone

66
Q

3 types of covalent modification (activate or repress transcription)

A

-phosphate group
-methyl group ( repression)
-acetyl group (activation)

67
Q

control of transcription needs 2 regulatory elements

A

-core promoter: physically linked to gene, binding site for basal transcription apparatus
-regulatory promoter: upstream of the core promoter, binding site for additional transcriptional activator proteins

68
Q

the basal transcriptional apparatus

A

-binds the core promoter
-made up of general transcriptional factors and RNA polymerase

69
Q

enhancer

A

a regulatory element that is not physically associated with the ore promoter

70
Q

silencers

A

-regulatory element that is recognized and bound by repressor proteins which repress transcription

71
Q

heat shock proteins (HSP)

A

-apart of coordinated gene regulation
-family of proteins made in response to stressful conditions in order to stabilize

72
Q

the amount of mRNA depends on the rate of its __ and __

A

-synthesis and degradation

73
Q

reverse transcription uses 2 elements

A
  1. retroelements (SINE and LINEs)
  2. elements derived from retroviruses
74
Q

reverse transcription

A

RNA to DNA

75
Q

normal transcription is ___ and uses the enzyme __

A

DNA to RNA
RNA polymerase

76
Q

transposable elements contribute to nearly __ of the human DNA

A

half

77
Q

retrotransposons are either ___ or ___

A

not LTR: SINE, LINE
LTR: endogenous retroviruses

78
Q

SINE and the predominant type

A

short interspersed nuclear elements
-Alu (looks like upside down pie)

79
Q

LINE and the predominant type

A

-Long interspersed nuclear elements
-L1

80
Q

insertion

A

-addition of 1 or more nucleotides

81
Q

deletion

A

-deletion of one or more nucleotides

82
Q

Alu does what?

A

-makes copies for chromosomes

83
Q

2 types of cell mutations

A

-somatic
-germinal (germ cell)

84
Q

somatic cell mutations

A

-in body cells
-cannot be passed to offspring
-may cause change in phenotype
-potential to cause cancer
-non-heritable

85
Q

germ cell mutations

A

-occurs in gametes
-does not affect the individual
-can be passed to offspring
-heritable

86
Q

if we share insertions among the population its called __

A

-fixed

87
Q

if we don’t share the insertions among the population it is __

A

-unfixed

88
Q

Common features of SINE or LINEs

A

-body
-poly A-rich stretch
-target site duplications (TSDs)

89
Q

SINE and LINEs exist as __

A

pairs

90
Q

1 SINE active and slowly goes __ but another is already behind, think of __

A

-extinct
-waves

91
Q

SINE functions

A

-does not encode any protein product
-non-autonomous: cannot copy or create copies

92
Q

LINE functions

A

-encodes protein products
-autonomous: can copy

93
Q

retrotransposition

A

copying of SINE/LINE insertions to new genomic locations via their RNA intermediate

94
Q

retrovirus

A

-RNA virus
-single stranded RNA genome
-enveloped by lipid membrane

95
Q

main steps of retroviral replication

A

-reverse transcriptase makes DNA from RNA
-the new DNA is integrated into the nuclear DNA of the host cell as a provirus
-provirus transcribed by host RNA polymerase (DNA to RNA)
-the new particles become assembled and become new viruses

96
Q

reverse transcriptase

A

-enzyme that mediates reverse transcription

97
Q

integrase

A

-enzyme that controls integration

98
Q

when viruses attach to a host cell the ___ proteins go to the ___ on the cell

A

-binding
-receptor

99
Q

germline infection of virus is passed by…

A

germline to offspring

100
Q

endogenous retroviruses are the only ___ within our DNA that undergo ___ ___ of the germline

A

-elements
-replication
-outside

101
Q

the 2 modes of evolution

A

-exogenous: outside he host, high mutation rate
-endogenous: part of the host genome, low mutation rate

102
Q

endogenous retroviruses can be shortened to

A

ERVs

103
Q

properties of ERVs

A

-originates from an infection of a germ cell from a retrovirus
-carries everything it needs for different tissues for integration

104
Q

(ERVs) integration into the host cell is

A

permanent

105
Q

provirus

A

the dsDNA inserted copy of the retroviral ssRNA in the host genome

106
Q

endogenous retrovirus is a provirus that…

A

has been transmitted to offspring

107
Q

structure of an ERV insertion

A

-body
-LTRs
-target site duplications (TSDs)

108
Q

all retroviruses have these 4 genes at least or more:

A

-gag
-pro
-pol
-env

109
Q

(ERVs) gag gene

A

-protects cell
-structural

110
Q

(ERVs) pro gene

A

-maturation

111
Q

(ERVs) pol gene

A

-reverse transcriptase
-integrase

112
Q

(ERVs) env gene

A

-fusogenetic (membrane fusion)
-receptor binding (recognizes and binds to receptors)

113
Q

HERV-K

A

-most recently integrated ERVs in humans
-unfixed
-expressed
-causes tumors and cell lines (breast and ovarian)

114
Q

polymorphic

A

-some unfixed insertions

genetics (20 decks)

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