Brainscape's Knowledge GenomeTM

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


See full index

Biology 242- Genomes and Evolution > exam 2 review > Flashcards

exam 2 review Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

prokaryotes

A

organisms whose cells lack a nucleus and other organelles

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

what does every organism require to drive reaction

A

source of energy
-light (photo)
-chemicals (chemo)

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

every organism requires what for synthesizing organic compounds

A

source of carbon
-CO2 or related compound (auto)
-organic carbon (hetero)

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

phototrophs

A

obtain energy from sunlight

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

chemotrophs

A

obtain energy from chemicals like iron

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

autrophs

A

need only CO2 or related compound as a carbon source to synthesize organic compounds

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

heterotrophs

A

need at least one organic nutrient source to synthesize organic compounds

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

auto means

A

CO2 or related compound

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

hetero means

A

organic carbon

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

which metabolic diversities are present in eukaryotes

A

photoautotroph and chemoheterotroph

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

what metabolic diversity are present in prokaryotes

A

-photoautroph
-chemautotroph
-photoheterotroph
-chemoheterotroph

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

energy source for chemoautrophs

A

inorganic chemicals

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

energy source for chemoheterotrophs

A

organic compounds

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

endosymbiosis

A

one organism lives inside the cell or cells of another organism

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

endosymbiont theory

A

Theory that mitochondria and plastids originated as prokaryotic cells engulfed by a host cell, The engulfed cell and its host cell then evolved into a single organism

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

how did chloroplast form from endosymbiosis

A

absorb photosynthetic prokaryote, then eventually became the chloroplast

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

how did mitochondria form form endosymbiosis

A

engulfed oxygen using prokaryote which over generations of cells became mitochondrion

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

what evidence supports the endosymbiont theory

A

-mitochondria and chloroplasts have their own DNA, ribosomes, double membranes
-mitochondria and chloroplasts replicate by binary fission
-DNA in mitochondria and chloroplasts similar to prokaryotes that had similar functions

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

what does the cell cycle consist of

A

interphase and mitotic (m) phase

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

when do chromosomes duplicate in cell cycle

A

S phase

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

true or false: cells spend the most tine in interphase

A

true

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

what does interphase include

A

cell growth and copying of chromosomes in preparation for cell division

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

what are the sub-phases of interphase

A

G1, S phase, G2

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

what is chromatin

A

combination of DNA and proteins

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

what does a chromosomes consist of

A

DNA molecule packed together with protein

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

how do chromosomes fit into the nucleus

A

through an elaborate multilevel system of packing

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

chromosome

A

thread like strands that contain genes

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

what proteins are responsible for the first level of packing in chromatin

A

histones

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

nucleosome

A

first level of packing in chromatin

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

allele

A

an alternate form of a gene, affects phenotype

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

during interphase, how is DNA usually found? what does it allow more of

A

-less condensed form called euchromatin
-allows more transcription

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

what can transcription machinery only work on

A

uncondensed DNA

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

what happens to DNA during mitosis and meiosis

A

DNA condenses into highly compact structures (chromsoomes)

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

homologous chromosomes

A

pair of chromosomes that have simaile but not identical genetic information. Carry same genes in same location, but have different alleles.

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

what is the highly condensed form of chromatin called

A

heterochromatin

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

what is n

A

number of distinct chromsomes

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

what is humans n

A

23

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

mitosis

A

cell division that results in diploid (2n) daughter cells with identical genetic information

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

sister chromatids

A

two identical copies of a single chromosome. They are identical to each other and the parent cell.

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

genes expressed in mitosis are

A

the same genes expressed in daughter cells as parent cells

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

meiosis

A

division that produces haploid (n) non identical daughter cells (gametes)

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

diploid

A

cell containing 2 sets of chromosomes, one from each parent

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

haploid

A

cell containing one set of chromosomes

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

gametes

A

haploid reproductive cells like an egg or sperm; unite during sexual reproduction to produce diploid zygote

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

G2 of interphase

A

metabolic growth and activity, preparation for cell division
-chromosomes uncondensed after being duplicated in s phase

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

centrosomes

A

structure that organize microtubles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

centriole

A

structure composed of microtubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

prophase

A

chromosomes condense (consist of two sister chromatids)
-mitotic spindles begin to form
-centrosomes move away from each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

prometaphase

A

-nuclear envelope fragments
-chromosomes condense further
-microtubules attach to kinetochores of chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

kinetochores

A

proteins on centromere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

metaphase

A

-centrosomes at opposite ends/poles of cell
-chromosomes arrive and line up at metaphase plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

how many sister chromatids are lined up at the metaphase plate in humans

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

anaphase

A

-sister chromatids split and become chromosomes
-chromosomes move towards opposite ends of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

telophase

A

-2 daughter nuclei form in the cell
-nuclear envelope arises from fragments of parent cell nuclear envelope and endomembrane system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

cytokinesis

A

division of cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

what is the eukaryotic cell regulated by

A

signaling molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

what can checkpoint signals influence

A

growth factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

growth factors

A

protein that stimulates other cells to divide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

What might happen if the cell ignored these checkpoints and progressed through the cell cycle?

A

The cell would divide under conditions where it was inappropriate to do so. If the daughter cells and their descendants also ignored either of the checkpoints and divided, there would soon be an abnormal mass of cells. (This type of inappropriate cell division can contribute to the development of cancer.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

G1 checkpoint absence of go-ahead signal

A

cell exits the cell cycle and enters a non dividing state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

G1 checkpoint if cell receives go ahead signal

A

the cell continues on cell cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

why durinh M checkpoint in cell in mitosis does cell receives stop signal

A

when any of its chromosomes are not attached to spindle fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

M checkpoint go ahead signal

A

-when all chromosomes are attached to spindle fibers and allows the cell to proceed into anaphase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

what happens in meiosis I

A

separates homologous chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

prophase I of meisosi

A

-spindle form, nuclear envelope fragments, chromosomes condenses
-chromosome pairs with homolog, allows crossing over at chiasmata
-microtubules attach to kinetochores at the centromere of each homolog

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

what happens in meiosis I but not mitosis

A

homologous chromosomes interact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

crossing over

A

exchange in genetic material on chromosomes

68
Q

chiasmata

A

x shaped region where crossing over has occurred in prophase i

69
Q

centromere

A

Region on sister chromatid (on duplicated chromosomes) where it is most closely attached to its sister by proteins

70
Q

what happens when centrosomes fuse, example?

A

leads to diversity and change in number of chromosomes among species
-chimps and humans have 2 chromosomes that fuse

71
Q

metaphase I of meiosis

A

-Pairs of homologous chromosomes align at the metaphase plate
-both chromatids of one homolog attach to kinetochore microtubules from one pole
-independent assortment

72
Q

independent assortment

A

1st meiotic division randomly sorts maternal and paternal homologs -> variation in offspring

73
Q

anaphase I of meiosis

A

-homologous chromosomes pulled apart towards opposite ends/poles of cell

74
Q

telophase I of meiosis

A

two haploid cells form, each chromosomes consist of two sister chromatids with regions of nonsister chromatid DNA

75
Q

what follows immediately after meiosis I

A

meiosis II

76
Q

difference between meiosis I and II

A

Meiosis I separates homologous chromosomes and meiosis II separates sister chromatids

77
Q

when does DNA replication occur in mitosis

A

s phase

78
Q

when does DNA replication occur in meiosis

A

occurs during interphase before meiosis I but not meiosis II

79
Q

number of divisions in mitosis

A

one

80
Q

number of divisions in meiosis

A

2

81
Q

synapsis of homologous chromosomes in mitosis

A

does not occur

82
Q

synapsis of homologous chromosomes during meiosis

A

occurs during prophase I

83
Q

number of daughter cells in mitosis and composition

A

2 identical to parent cell

84
Q

number of daughter cells in meiosis and composition

A

4 genetically different from parent cell

85
Q

roles of mitosis

A

enables multicellular eukaryotes to arise from single cell; growth and repair; asexual reproduction in some species

86
Q

roles of meiosis

A

produces gametes or spores; reduces number of chromosomes by half; introduces genetic variability

87
Q

what is synapsis

A

pairing of two homologous chromosomes that occur during meiosis

88
Q

where are operons found

A

prokaryotes

89
Q

operon

A

cluster of functionally related genes that can be simultaneously controlled by a single promoter with an “on-off switch”

90
Q

operator

A

portion of DNA that acts as the switch where repressesors attaches

91
Q

repressor

A

protein that inhibits transcription

92
Q

what is the function of the trp operson

A

turns the genes on and off the encode enzymes required to synthesize tryptophan

93
Q

how does binding with the corepressor tryptophan affect the conformation of the trp repressor

A

alters the conformation or 3D structure of the protein so that it can bind to the operator

94
Q

operator composition

A

DNA

95
Q

repressor composition

A

protein

96
Q

enzyme 2 (c) composition

A

protein

97
Q

trpC compoistion

A

DNA

98
Q

trp operon transcript composition

A

mRNA

99
Q

when environmental tryptophan is low trp operon is active or inactive

A

active

100
Q

when environmental tryptophan is low trp repressor is active or inactive

A

inactive

101
Q

when environmental tryptophan is low the trp repressor is in

A

non-functional conformation in the cytoplasm

102
Q

order these
_enzyme c is synthesized and folds into its functional form
-mRNA transcript is produced
-intracellular tryptophan increases

A

1)mRNA transcript is produced
2)enzyme c is synthesized and folds into its functional form
3) intracellular tryptophan increases

103
Q

when environmental tryptophan is High trp operon is active or inactive

A

inactive

104
Q

when environmental tryptophan is High the trp repressor is active or inactive

A

active

105
Q

when environmental tryptophan is High the trp repressor is bound

A

to the operator

106
Q

when environmental tryptophan is High what happens to RNA polymerase

A

it is blocked form proceeding with transcription down the length of the operon

107
Q

when environmental tryptophan is High concentration of mRNA for operon genes after the operon is repressed

A

decreases

108
Q

when environmental tryptophan is a High concentration of copies of the protein coded by trp c after the operon is repressed

A

decreases

109
Q

when environmental tryptophan is High concentration intracellular tryptophan after the operon is repressed

A

decreases

110
Q

A mutation in the trp repressor gene results in a repressor that can bind Trp, but cannot bind to the operator. What effect would this mutation have?

A

Transcription will proceed because the repressor cannot bind to the operator to block transcription. Trp mRNA and enzymes will continue to be made, resulting in an ever-increasing concentration of trp.

111
Q

After a sufficient amount of time, the bacteria has a fully functioning set of enzymes producing tryptophan (Trp). If the bacteria produces more Trp than they use in synthesizing proteins, what happens to the intracellular Trp concentration and what effect does this have on the activity of the trp operon?

A

The intracellular trp concentration will increase until it binds to the repressor, blocking transcription of mRNA, translation of trp enzymes, and production of more trp.

112
Q

. A mutation in trpC results in a non-functional enzyme. What effect do you expect on the
On the concentration of intracellular tryptophan? Production of trp operon mRNA?

A

Intracellular trp will decrease until there is none left or until the bacterium can take it up from the environment. Production of the trp operon mRNA will proceed once there is not enough intracellular trp available to bind to the repressor. The transcript encodes for the enzymes including trpC although no trp is made because the biosynthetic pathway cannot proceed properly.

113
Q

with repressible operon but transcription is usually on but can be repressed when

A

a specific molecule binds to a repressor

114
Q

active repsossor

A

bound to operator preventing transcription

115
Q

inactive transcription

A

not bound to operator

116
Q

with inducible operon transcription is usually off but

A

can be induced when a specific molecule binds to repressor

117
Q

anabolic pathway

A

metabolic pathway that consumes energy to synthesize a complex molecule from simpler molecules

118
Q

how are anabolic pathways controlled

A

repressible operon

119
Q

energy from repressing the genes involved in biosynthesis when the end product is plentiful

A

saves energy

120
Q

catabolic pathway

A

metabolic pathway that releases energy by breaking down complex molecules to simpler molecules

121
Q

what are catabolic pathways controlled by

A

inducible operon

122
Q

energy after inducing the genes involved in breaking down particular molecule only when that molecule is present

A

saves energy

123
Q

genomes are ____ within all the cells in an organism

A

identical

124
Q

what do differences between cell types result from

A

differential gene expression

125
Q

differential gene expression

A

the expression of different sets of genes by cells with the same genome

126
Q

true or false: all cell within an organism contain the same DNA

A

true

127
Q

cell theory

A

All cells within an individual organism typically contain the same DNA, with some exceptions (such as immune system cells and germ cells), because they originate from a single fertilized egg (zygote) through a process called cell division

128
Q

how does chromatin modification regulate gene expression

A

structural organization
-genes within highly packed heterochromatin are not usually expressed

129
Q

true or false: genes within highly packed heterochromatin are generally expressed

A

false

130
Q
A
131
Q

histone acetylation

A

addition of an acetyl group to histone tail amino acids opens up chromatin and promotes transcription

132
Q

what does addition of methyl groups condense chromatin inhibit

A

transcription

133
Q

exon

A

expressed sequence, encodes protein

134
Q

intron

A

intervening sequence that get removed, do not encode protein

135
Q

upstream

A

before promoter

136
Q

downstream

A

after promoter

137
Q

control elements

A

segments of noncoding DNA that serve as binding sites for transcription factors

138
Q

enhancer

A

segment of eukaryotic DNA containing multiple control elements, usually located far from genes whose transcription it regulates

139
Q

poly-a-tail

A

sequence of 50-250 adenine nucleotides added onto the 3’end of pre mRNA

140
Q

GTP cap

A

molecule added to 5’ end of eukaryotic mRNA which contributed to mRNA stability and processing

141
Q

what is a transcription factor

A

a protein that promotes transcription

142
Q

what is an example of general transcription factor

A

initiation complex

143
Q

what is an example pf specific transcription factor

A

activators

144
Q

general transcription factors

A

essential for the transcription of all protein-coding genes and initiate transcription

145
Q

specific transcription factors

A

regulate gene expression of specific genes by binding to specific regions of those genes

146
Q

what events trigger transcription

A

binding of the activator to proteins in the transcription initiation complex

147
Q

roles of transcription factors

A

1) activator protein bind to distal control elements grouped as an enhancer in DNA
2)DNA bending protein brings the bound activators closer to the promoter
3)activators bind to some mediator proteins and general transcription factors, forming an active transcription initiation complex on promoter

148
Q

mRNA processing only happens in

A

eukaryotes

149
Q

how does regulation of gene expression in eukaryotes differ from regulation in bacteria

A

gene expression in bacteria is more simple and efficient and does not require coordination across different segments of DNA and as many moving parts (transcription imitation complex factors, as much cell signalling, mRNA proccessing) as eukaryotes.

150
Q

how much of human genome encodes a protein

A

1.5%

151
Q

cytoplasmic determinants come from

A

the mother

152
Q

cytoplasmic determinants

A

A maternal substance, such as a protein or RNA, that when placed into an egg influences the course of early development by regulating the expression of genes that affect the developmental fate of cells

153
Q

what causes cell differentiation in an early embryo

A

induction

154
Q

induction

A

cells from one area of embryo influence another area via signals that affect gene expression

155
Q

indcution can control the assignment of

A

body axes

156
Q

master regulatory gene

A

a regulator gene at the top of a gene regulation hierarchy, particularly in cell differentiation

157
Q

homeotic genes

A

any of the master regulatory genes that control placement and spatial organization of body parts in animals, plants, and fungi by controlling the developmental fate of groups of cells

158
Q

hox genes are a type of

A

homeotic gene

159
Q

what do hox genes hep with

A

correct positioning of body parts

160
Q

where does expression of genes begin

A

anterior

161
Q

homeobox found in

A

found across different invertebrates and vertebrates in the same organization on chromosomes

162
Q

hox genes are ______ __________ genes and largely determine the final body plan of every animal species

A

highly conserved

163
Q

enhancer

A

segment of DNA containing group of distal control elements

164
Q

What kind of proteins do Hox genes encode?

A

transcription factprs

165
Q

what do these genes do

A

Encode transcription factors that promote transcription of genes within specific body segment that encode a complex of proteins required to build a specific structure (antennae)

166
Q

what do hox genes tell us about why all bilateral animals have similar body plans

A

Hox genes are highly similar across bilateral animals and must have been present in a common ancestor of bilateral animals

Biology 242- Genomes and Evolution (35 decks)

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