Brainscape's Knowledge GenomeTM

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


See full index

biology 1001 > cumulative final review > Flashcards

cumulative final review Flashcards

1
Q

1: why is virus sometimes considered living, and sometimes not?

A

virus is an obligate parasite (not on tree of life)

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

1: evolution of drug resistance in HIV

A

random mutations create variations in AZT resistance
high rate of mutation due to reverse transcriptase enzyme

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

1: characteristics of scientific theory

A

must be both testable and falsifiable (some possible observation or experimental finding could prove the theory to be wrong)

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

1: evolution is variational/transformational?

A

variational: populations evolve, individuals do not.

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

change through time

A

change over a long period of time. allele frequencies in a population change from one generation to the next. (due to environmental pressures?)

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

common ancestry

A

all life is related through common ancestry

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

speciation

A

creation of a new species. species can reproduce with viable, fertile offspring

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

gradualism

A

species evolve through slow continuous changes without significant interruption

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

natural selection

A

organisms that are better fitted to their environment are more likely to survive and pass on their genes to their offspring.

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

G1 phase

A

period of growth before DNA replicates. gap where no DNA is synthesized, cell continues to function

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

S phase

A

DNA replication and chromosome duplication occur. continues synthesis of other cellular molecules

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

G2 phase

A

second gap where cell growth continues and cell prepares for mitosis. no DNA synthesis, continues to synthesize RNAs and proteins. marks the end of interphase

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

G1-S checkpoint

A

before replication, ensures mutations are not duplicated, if severe DNA damage then cell proceeds to G0 phase

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

G-M checkpoint

A

ensures that cell is prepared for mitosis. all necessary conditions are met to prevent errors in chromosomes segregation and cell division

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

mitotic spindle checkpoint

A

ensures equal distribution of sister chromatids to minimize the risk of aneuploidy

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

2: positive regulation

A

phosphorylation cascade - cyclins and CDKs
cyclin binds to CDK
cyclin-CDK complex is phosphorylated
activated cyclin-CDK complex phosphorylates target protein
phosphorylated target protein changes to active form. moves cell into next stage of cell cycle

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

2: negative regulation

A

p53 detects DNA damage and increases p21 (cyclin-CDK inhibitor) production which blocks phosphorylation of cyclin CDK. stops cell cycle

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

2: why is meiosis I reductional and meiosis II equational?

A

meiosis I: 2n → n
meiosis II: n →n

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

2: mechanisms giving rise to variation in meiosis

A

homologous recombination - crossing over at the chiasma
independent assortment - dependent on equatorial arrangement
random fertilization - any haploid cells could fuse

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

aneuploidy

A

abnormal number of chromosomes

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

2: products of life cycle in animals

A

zygote (2n) → animal (2n) (mitosis)
animal (2n) → gametes (n) (meiosis)

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

2: products of life cycle in plants and fungi

A

zygote (2n) → sporophyte (2n) mitosis
sporophyte (2n) → spores (n) meiosis
spores (n) → gametophyte (2n) mitosis

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

2: products of life cycle in fungi and algae

A

zygote (2n) → spore (n) meiosis
spore (n) → gametophyte (n) mitosis
gametophyte (n) → gametes (n) mitosis

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

3: n-value and coefficient of n

A

n-value: number of unique chromosomes present in an organism
coefficient of n (ploidy): number of unique sets present in an organism

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

3: C-value and coefficient of C

A

C-value: amount of DNA in one set of chromosomes, genome size
coefficient of C: how many time the entire genome is present in a cell

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

3: correlation between n and C, implications on complexity?

A

n and C are not correlated nor do they dictate complexity in an organism

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

semi-conservative DNA replication

A

old strand is template for synthesis for new strand.

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

cell senescence

A

irreversible cell cycle arrest. G0 phase, no longer replicates or divides

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

Hayflick limit

A

number of times a cell divides before cell division stops

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

3: mechanism of telomerase action

A

telomerase restores length of telomeres.

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

3: why do only cancerous and germ cells express telomerase?

A

telomerase could cause a problem in somatic cells (mutations)

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

4: types of DNA damage

A

exogenous, endogenous

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

4: exogenous DNA damage

A

outside, from environment, damages DNA directly.
UV light, chemicals (smoking medication, air pollution), ionizing radiation

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

4: endogenous DNA damage

A

inside cell
ROS, replication errors

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

4: mechanism of ROS

A

IR splits H2O
very unstable and electronegative
steals electrons → damage to cell
oxygen paradox
repaired by NHEJ

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

4: mechanism of proofreading

A

DNA polymerase III corrects itself (exonuclease activity)

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

4: mechanism of mismatch repair

A

mismatch repair proteins detect errors and excise and correct incorrect nucleotide

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

4: mechanism of NHEJ

A

non-homologous end joining.
repairs double strand breaks
could introduce errors → mutation

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

4: types of point mutations (3)

A

substitution: single nucleotide is replaced by another
silent - no effect on amino acid sequence
missense - changes one amino acid, potentially affecting function and structure of protein
nonsense - introduces stop codon leading to truncated polypeptide

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

4: frameshift mutations (2)

A

insertion or deletion - addition or removal of nucleotides alters genetic sequence. often leads to truncated protein

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

4: chromosomal mutations (2)

A

inversion - segment of chromosomes is reversed in orientation, potentially disrupting gene function
translocation - segments of DNA are exchanged between non-homologous chromosomes, potentially disrupting gene expression

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

4: thymine dimers

A

distort the backbone and halt DNA polymerase (not a mismatch)
caused by UV, repaired by excision repair in humans and by photolyase and white light in other species

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

4: role of tautomeric shifts in mutagenesis (process where DNA changes resulting in a gene mutation

A

normal pairing favoured, has different preferred partner when tautomeric form shifts. can result in mutation

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

4: transposable elements

A

portion of genome that copy/cut and paste somewhere else

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

4: regulatory role of transposable elements

A

responsible for increases in genome size.

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

4: genome composition

A

55% transposons, viral sequences, dead genes (junk)
25% unknown (junk?)
10% essential (2% coding)
10% intron (junk)

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

5: epistasis and how it differs from Mendelian genetics

A

expression of one gene masks the expression of another gene at a different locus. results in complex inheritance patterns that do not conform to the simple dominance and recessiveness observed in classics Mendelian genetics

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

6: genotypic frequency

A

distribution of genotypes in a population

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

6: allele frequency

A

distribution of a specific allele in a population

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

6: conditions of Hardy-Weinberg Equilibrium (5-6)

A

no mutations, all genotypes are equally fit, closed population (no gene flow or migration), infinite population size, random mating)

51
Q

6: absolute fitness (W)

A

average number of surviving offspring for each genotype

52
Q

6: relative fitness (w)

A

absolute fitness of one genotype divided by the absolute fitness of the most fit genotype

53
Q

6: selection against dominant allele

A

removed from population over time

54
Q

6: selection against recessive allele

A

decreases but never fully goes away (can hide in heterozygotes)

55
Q

6: mechanisms of microevolution (agents of evolution) (5)

A

mutations
non-random mating
gene flow
genetic drift
natural selection

56
Q

gene flow

A

organisms or their gametes sometimes move from one population to another and may introduce novel alleles into a population, shifting its allele and genotype frequencies away from the values predicted by H-W

57
Q

genetic drift

A

allele frequencies change from one generation to the next simply by chance
ex. founder, bottleneck effect

58
Q

6: directional selection

A

shifts a trait away from the existing mean and towards the favoured extreme
most cases of artificial selection are directional

59
Q

6: stabilizing selection

A

individuals expressing intermediate phenotypes have the highest relative fitness
most common mode of natural selection. reduces genetic and phenotypic variation and increases frequency of intermediate phenotypes

60
Q

6: disruptive selection

A

extreme phenotypes have higher relative fitness than intermediate phenotypes
less common than directional and stabilizing selection

61
Q

7: why sex?

A

allows us to make new multilocus combinations of alleles by meiosis

62
Q

7: dioecious

A

exclusively male or female
cross-fertilization between male and female individuals necessary for sexual reproduction

63
Q

7: monoecious

A

both male and female reproductive parts (in same plant). organism can carry out both functions involved in sexual reproduction

64
Q

7: hermaphrodite

A

both male and female reproductive parts (in same flower)

65
Q

7: risks of selfing

A

negative effects of inbreeding

66
Q

7: why sexual reproduction over asexual

A

removes harmful alleles and diversifies variety of offspring. increases chances of surviving in unstable conditions (advantageous traits)

67
Q

7: intrasexual selection

A

competition between individuals of the same sex

68
Q

7: intersexual selection

A

choose mate based on certain traits or behaviours displayed by opposite sex

69
Q

8: morphological species concept

A

members of a species share similar physical traits that distinguish them from individuals of other species

70
Q

8: biological species concept

A

members of a species can interbreed and produce viable, fertile offspring under natural conditions

71
Q

8: phylogenetic species concept

A

shares a common ancestor and same branch on phylogenetic tree

72
Q

8: prezygotic isolating mechanisms

A

ecological - species live in different habitats
temporal - species breed at different times
behavioural - species cannot communicate
mechanical - species cannot physically mate
gametic - species have nonmatching receptors on gametes

73
Q

8: postzygotic isolating mechanisms

A

hybrid inviability - hybrid offspring cannot produce gametes
hybrid sterility - hybrid offspring cannot produce gametes
hybrid breakdown - hybrid offspring have reduced survival or feritility

74
Q

8: allopatric speciation

A

between geographically isolated species
gene flow prevented
genetic differences - may cause reproductive isolation

75
Q

8: sympatric speciation

A

same geographic area
reproductive isolation, potentially leading to the formation of a new species

76
Q

8: secondary contact, reinforcement

A

two previously geographically isolated populations reunite. natural selection strengthens prezygotic barriers to reproduction between two divergent populations

77
Q

9: use of phylogenetic tree

A

used to show evolutionary relationships between organisms

78
Q

9: how to find common ancestor on phylogenetic tree

A

find the branching point of the two species. the more recent the branchign points are, the more closely related the two species are

79
Q

9: monophyletic grouping given a phylogenetic tree

A

monophyletic: includes all descendants of MRCA of the group
non-monophyletic: includes descendants that aren’t from the most recent ancestor

80
Q

homology

A

similarity that reflects common ancestry

81
Q

convergence

A

not closely related organisms develop similar features through evolution

82
Q

homoplasy

A

misleading similarities or dissimilarities, not due to common ancestry

83
Q

9: principle of parsimony

A

simplest approach is best. minimize number of homoplasies. tree with fewer evolutionary changes will be most parsimonious

84
Q

9: derived

A

character states that are new in descendants

85
Q

9: ancestral

A

character states that were present in the ancestors of a clade

86
Q

9: anagenesis

A

single species gradually undergoes evolutionary change over time into a different, more advanced form without formation of separate species

87
Q

9: cladogenesis

A

single species diverges into two or more distinct species. increases biodiversity

88
Q

9: evolutionary systematics

A

classifies and organizes organisms based on their evolutionary relationships

89
Q

10: intraspecific interaction

A

interactions between individuals of the same species

90
Q

10: interspecific interactions

A

interactions between individuals of different species

91
Q

10: interference/contest competition

A

one organism has resource and another will fight to take it (dangerous, either party has a chance of getting hurt)

92
Q

10: exploitation/scramble competition

A

2 or more organisms use the same resource, one uses more than others (free for all)

93
Q

10: symbiosis

A

close and long term association between 2 species

94
Q

10: symbiotic relationships (5)

A

mutualism(+/+)
commensalism (+/0)
predation (+/-)
parasitism (+/-)
herbivory (+/-)

95
Q

10: mutualism

A

both species benefit from the association

96
Q

10: commensalism

A

one species benefits from the association but the other is unaffected

97
Q

10: predation

A

only one species benefits from the association and the prey is injured or killed (two strategies: sit and wait, active pursuit)

98
Q

10: parasitism

A

only one species benefits from the association
affects fitness of the host, but doesn’t result in its direct death

99
Q

10: parasitoids

A

when an adult is free living, but its offspring develop in or on the host and kill it

100
Q

10: herbivory

A

similar to parasitism but between herbivores and plants
affects fitness of plant but doesn’t result in its direct death

101
Q

10: simple (direct) parasitic life cycle

A

parasite species uses one host species to complete life cycle and survive

102
Q

10: complex (indirect) parasitic life cycle

A

parasite species uses at least 2 different host species to complete life cycle and survive

103
Q

10: host manipulation by parasites and parasitoids

A

parasite-induced alteration of a host’s phenotype that increases parasite fitness. improves probability of transmission

104
Q

10: red queen hypothesis

A

species must constantly adapt and evolve in competition with other evolving organisms. environment is constantly changing

105
Q

10: continuous arms race

A

ongoing competition between different species in an ecosystem, where each species evolves adaptations and counter-adaptations to gain an advantage. can only be a result of chance mutations

106
Q

10: adaptations to reduce enemy impact (10)

A

physical
behavioural
autonomy
chemical
camouflage
mimesis
bodyguards
herd effect
detection of predators
synchronized emergence

107
Q

10: ecology of fear

A

interactions with predators may not result in death, it can change behaviours

108
Q

10: keystone species

A

removal of a keystone species in an ecosystem can lead to a disruption of the entire food web

109
Q

10: intraguild predation

A

species compete for same prey and would benefit from preying upon potential competitors

110
Q

11: anthropocene

A

current geological age in which humans have been the dominant factor on climate and the environment. started by the industrial revolution

111
Q

11: tipping point

A

1.5C, point of no return for irreversible climate change

112
Q

11: increasing climate trends (7)

A

global surface temperature (land and ocean)
ocean heat content
carbon dioxide
sea level
methane
nitrous oxide
specific humidity

113
Q

11: decreasing climate trends (3)

A

arctic and antarctic sea ice extent
global glacier mass balance
greenland ice sheet mass balance

114
Q

11: drought conditions

A

decreased foraging
decreased flower availability
higher nectar viscosity
more competition with resident nectivores

115
Q

11: selection effects of a changing environment

A

peppered moths and univoltine (know specifics)

116
Q

11: gradual change

A

climate change - opportunity for adaptation or slow displacement

117
Q

11: sudden change

A

extreme weather events - no opportunity for adaptation

118
Q

11: tropicalization

A

movement of organisms in response to warmer temperatures from tropical (warmer) to temperate (cooler) environments
effects on food chains, gain/loss of genetic diversity, hybridization

119
Q

11: geographical changes (3)

A

latitudinal
altitudinal
aquatic depth

120
Q

11: latitudinal change

A

species’ geographic range can become more North/South over time (tropicalization)

121
Q

11: altitudinal change

A

ex. tropical birds are moving to higher altitudes as a result of climate change

122
Q

11: aquatic depth

A

distribution of species is changing according to sea levels

123
Q

11: asynchrony

A

species present at a different time that its food source

biology 1001 (13 decks)

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