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Flashcards in Midterm 1 Deck (128)
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1
Q

recondite

A

understood only by experts or requiring detailed specialized knowledge to be understood only by experts. dealing with difficult material

2
Q

incredulous

A

unwilling to belive or unconvinced by something showing or characterized by disbelief

3
Q

idolent

A

lethargic and not showing interest or making any effort

4
Q

Boor

A

rude obnoxious, ill mannered, crass person

5
Q

stultify

A

to diminish somebodies interest and lively state of mind being repetitive tedious or boring

6
Q

iconoclast

A

one who challenges traditional belief, customs or values or goes against established practice

7
Q

salubrious

A

beneficial to ones health

8
Q

Nihilist

A

someone who believers that nothing is worthwhile or that life is pointless and all human values are worthless, completely disregards established conventions, rules or believes

9
Q

lurird

A

sickening, horrifying or shocking: sensational, with graphic horror , devastation or violence

10
Q

desultory

A

pointless or aimlessly passing for one thing or place or than other, random

11
Q

parable

A

a simple story to illustrate a moral or spiritual lesson

12
Q

redolent

A

strongly suggestive of smell, having a well defined odor

13
Q

lilliputian

A

a person or thing that is unusually small

14
Q

incorrigible

A

impossible to change or correct, often referring to someone who is unruly and impossible to manage

15
Q

purulent

A

contain or excluding puss

16
Q

inveterate

A

fixed in habit or practice or firmly establishes and of long lasting

17
Q

ingrate

A

an ungrateful person; somebody who does not show gratitude

18
Q

venerable

A

high respected, revered

19
Q

gesticuate

A

an expression/gesture with your hands

20
Q

magnanimous

A

noble-spirited, generous, kind and forgiving

21
Q

imprecate

A

cures, to put something or someone down, to call harm on something or someone

22
Q

nefarious

A

completely wicked and immoral

23
Q

egregious

A

bad to an extraordinary and outrageous degree

24
Q

evolution

A

decent with modification, changes in population allele frequency

25
Q

homology

A

similarity resulting from common ancestry, often despite differences in function

26
Q

analogy

A

similarity in function but not having the same evolutionary origin

27
Q

can selective breading lead to evolution?

A

by selectively breeding mice for the ability to run over 24 generations, the results show that the selected group ran 2.78 times as far than the control

28
Q

microevolution

A

small evolutionary changes within species or populations

29
Q

speciation

A

lineages split and diverge an ancestral species can give rise to two or more dependent or daughter species

30
Q

macoevolution

A

referring to larger phenotypic changes sufficient to place an organism in a different higher taxon. over time microevolution results in both speciation and macroevolution

31
Q

incipient species

A

finishing the final stages of speciation

32
Q

vestigial structures

A

useless in one species but is important in an ancestor species

33
Q

explain the case of vestigial features in the Stickleback fish

A

the marine form is fully armoured. a lake was poisoned to remove all the fish and the marine form was able to move into the lake. the lake favoured the lightly armoured fish b/c it allowed more energy to be used for reproduction

34
Q

define species

A

species are groups of interbreeding natural populations that are reproductively isolated from other such groups - individuals within a species resemble each other due to gene flow resulting from interbreeding

35
Q

what are ring species

A

a connected series of neighbouring populations where adjacent populations are still able to inter breed. but there are at least two populations of the “ends” of the “ring” that are unable to interbreed - The Siberian Greenish Warbler

36
Q

the law of succession

A

fossils in a given geographic region are more closely related to the extant fauna of that region than they are to organisms in a different geographic region

37
Q

evidence for homology

A

studies in comparative anatomy, embryology, physiology, and genetics revealed strong similarities across organisms

38
Q

how did developmental homology resulted in male hernias

A

in the embryo the testes are positioned high up and eventually descend into the scrotal sac, this leaves a weakening in the abdominal wall where the intestine and protrude

39
Q

principle of superposition

A

younger geological layers sit on top of older ones

40
Q

principle of original horizontality

A

lava and sedimentary rocks were originally laid down in the horizontal position

41
Q

principle of cross cutting relationships

A

rocks the intrude into other rocks are younger than the host rocks

42
Q

principle of inclusion

A

boulders or other fragments found in a rock body are older than their host rocks

43
Q

principle of Faunal succession

A

more recent fossils are more similar to existing life forms than older fossils

44
Q

natural selection

A

differences in the survival and reproduction of phenotypes, leading to differences in their contribution to the next generation, resulting a change in frequency of heritable phenotypic variations.darwin was not the first one to propose evolution. he developed a mechanism that explains how evolution can occur

45
Q

components of natural selection

A

living things produce more offspring than can be supported, there is constant struggle for life, individuals in a population vary in their phenotypes, some of this variation is heritable, those individuals who are best adapted to the current conditions are most likely to survive and reproduce, if these adaptions are heritable they will be passed on to offspring. natural selection acts on phenotypes but only if there is a change in allele frequencies not population genotype frequency

46
Q

evolutionary fitness

A

refers to an individuals contribution to the next generation in terms of number of offspring, the more offspring an individual contributes to the next generation, the greater the individuals evolutionary fitness

47
Q

what is contributes to fitness

A

viability or mortality selection: an individuals ability to survive and reach reproductive age
sexual selection: an individuals ability to procure a mate
fecundity selection: family size, which is usually measured as the number of female gametes/eggs are produced

48
Q

adaption

A

is a trait or characteristic that increases an individuals fitness, in comparison to individuals that do not have that trait
natural selection results in adaptive evolution

49
Q

what are darwin’s four postulates

A
  1. individuals within species are variable
  2. some of these variations are heritable
  3. more offspring are produced than survive, some are more successful at survival and reproduction
  4. the survival and reproduction of individuals is not random, those who reproduce the most are those with the most favourable variations and are naturally selected
50
Q

how did the introduction of the cane toad evoke natural selection

A

toads had skin glands that make toxic substances, predators that were able to eat the frogs dies off in large numbers.
snakes with large jaws and stout bodies ate the toad and dies, snakes with smaller jaws and slandered bodies could not and survived .
there was a decrease in law sizw and increase in slenderness

51
Q

how does natural selection operate

A

NA acts on individuals but consequences are in the populations
nNS acts on phenotypes but evolution consists of changes in allele frequ.
NS id backwards looking, can produce new trains in conjunction with mutation,
NS does not lead to perfection, is nonrandom but not progressive,
acts on individuals not groups

52
Q

antagonistic selection

A

when one component of fitness is at adds with another. ex: male peacock feathers are large and require a lot of energy, they they weigh organism down making them easy targets

53
Q

human induces selection regimes

A

harvesting practices can impose selection on populations unintentionally
ex: sheep with horns greater then a specified size can be hunted, typically males with large horns are killed prior to breeding giving them a reduced fitness
directional selection for smaller horn sizes

54
Q

evolution of antibiotic resistance

A

When individuals don’t complete their dose leaves microbs that hare more resistance to antibiotic - those go off and reproduce making large populations of resistant

55
Q

types of variation

A

genetic variation: can possess different phenotypes as a result of genetic differences/ different genotypes
environmental: different phenotypes as a result of exposure to different environment despite identical genotypes
genotype by environment interactions: different phenotypes as a result of the interactions of their genotype with the environment

56
Q

example of environment integration producing variation

A

in many reptiles sex is determined by the temp. at which the egg develops. individuals at warm or cool tend to be female while at intermediate temps tend to be male

57
Q

example of environmental variation

A

when genetically identical Daphnia were places in habitats with and without phantom midge predation the individuals exposed to predation developed defences

58
Q

phenotypic plasticity

A

refers to the fact that genetically identical individuals can have different phenotypes in different environmental conditions

59
Q

reaction norm

A

refers to the patter or range of phenotypes that the same genotype can posses as a result of different environments

60
Q

mutation

A

any heritable change in the genetic material. is the ultimate source of all genetic variation, provides the raw material for other evolutionary forces such as NA and genetic drift to act on.

61
Q

point mutations

A

single base pair changes, transitions are more common than transversions
can be synonymous (dont change AA) or non-synoymous

62
Q

indels

A

refer to the insertion or deletion of one or more nucleotides in a DNA sequence, and frequency, result in frameshift

63
Q

neutral mutations

A

have no effect on fitness

64
Q

deleterious mutations

A

reduce fitness

65
Q

beneficial or advantageous mutations

A

increases the fitness

66
Q

lethal mutations

A

a deleterious mutation that results in the organisms death before reproduction

67
Q

example of heterozygote superiority

A

those heterozygous for the sickle cell and normal are resistant to malaria, homozygous for normal allele are susceptible to malaria.

68
Q

heterozygote superiority

A

the heterozygote has a greater fitness than the homozygotes

69
Q

is the mutation rate subjected to NS

A

mutation rate is heritable, mutations in DNA pol can effect these rates as can mutations in the genes responsible for repairing BP mismatches.
high mutation rates is beneficial in poorly adapted environments. if individuals are well adapted most mutations will be deleterious

70
Q

gene duplication

A

result in loci that retain their function, gain a new function or become a pseudogene and importantly, has also resulted in the evolution of gene families
caused by unequal crossing over.

71
Q

inversion mutations

A

result from ionizing radiation and typically involve large regions of chromosomes, affect linkage and gene order

72
Q

genetic cline

A

an increase of decrease in the frequency of a gene over geographic distance

73
Q

polyploidy

A

large scale mutations- duplication of entire sets of chromosomes. occurs in organisms that can self fertilize or when different species hybridize.
caused by errors in meiosis resulting in diploid gametes

74
Q

why is polyploidy important

A

it can result in new species being found
doubled chromosomes can gain new functions allowing adaption
important source of genetic variation in natural populations - in flowering plans polyploid formations occur as commonly as point mutations

75
Q

what is the classical hypothesis

A

populations contain very little variation, selection maintains a single best allele at any locus, and heterozygotes are rare. heterozygotes occur as a result of rare deleterious mutations that are quickly eliminated by selection

76
Q

what is the balance hypothesis

A

individuals are heterozygous at many loci and balancing selection maintains lots of genetic variability

77
Q

define balancing selection

A

any form of selection that results in the maintenance of genetic variability

78
Q

evidence for the balancing model

A

protein electrophoretic studies revealed substantial genetic variation

79
Q

what is the selection hypothesis

A

balancing selection results in the maintenance of high genetic variability - heterozygotes tend to have a higher fitness

80
Q

what is the neutral hypothesis

A

most alleles in natural populations are neutral and dod not affect fitness

81
Q

define genotype frequency

A

of individuals of a genotype/N - must add up to 1

82
Q

how to calculate allele frequ.

A

2(AA) + (AB) / N

2(BB) + (AB) / N

83
Q

what is the hardy - weinberg principle

A

shows us how allele and genotype frequ. behave in natural populations if there are no violations and the population is randomly mating - allows us to predict genotype frequ. from allele

84
Q

what is a panmictic population

A

a sexually reporducing populations where each male has an equal probability of mating with each female and each female has an equal probability of mating with with each male

85
Q

modeling random mating

A

assuming that genotype frequ. are the same among male ands female and the population is infinitely large , the probability for a given individual to mate with one of a certain genotype is equal to the genotype frequ.

86
Q

what is the probability that two gametes unite

A

is equal to the product of the allele frequ.

p^2 qp q^2

87
Q

what are the assumptions of the HW principle

A

no selection, no mutation, no migration, infinitely large with panmictic mating, population is diploid, population is reproducing sexually

88
Q

what does HW teach us

A
  1. is a population is out of equilibrium, it will take a single generation of random mating to restore equilibrium
  2. if there are no violations, the HW principle shows that the genotype and allele frequ. will not change
89
Q

rejecting the null hypothesis

A

is the calculated X^2 is less than critical value there is no statistical evidence to reject the null

90
Q

what is heterozygote deficit

A

if the observed heterozygosity is less then expected

91
Q

what are the modes of selection

A

directional: increase or decrease of the mean, reduced variation
stabilizing: those at both extremes have low survival, no effect on the mean decrease in variation
disruptive: individuals at extremes have a high survival, no effect on mean, increases variation

92
Q

explain the case of the goldenrod gall

A

stabilizing selection, if the gall is too small it parasitized by wasps if too big birds

93
Q

why do natural populations exhibit significant variation and why is it maintained

A
  1. populations are not in evolutionary equilibrium with respect to directional or stabilizing selection
  2. in most populations there is a balance b/w mutation and selection
  3. disruptive selection may be more common than thought
94
Q

what is the effect of mutation on HW

A

mutation will not result in disequilibrium b/c as long as there is random mating mutated gametes will unite and the zygotes will in equilibrium based on the new frequency
has a small impact on allele frequ.

95
Q

selective sweep

A

the rapid fixation of a beneficial allele by selection

96
Q

migration

A

geen flow, movement of alleles b/w populations after migration there is a change in allele frequ. and the genotype frequ. arnt consistent with HW

97
Q

in the case of the banded snakes, what is the effect of migration?

A

the island favours the unbanded, but migration maintains the banded population,
tends to homogenize population in terms of allele frequ

98
Q

what is F_st

A

the fixation index, measure of how much a population differ in allele frequ. when equal to 0 the frequ are equal at 1 there are no common alleles

99
Q

What is genetic drift

A

the chance fluctuations in an allele frequ. as a result of random sampling gametes b/c zygotes are produced from a random sample of gametes from the initial pool, allele frequ. can change as a consequence of this sampling error.

100
Q

does genetic drift result in disequilibrium

A

no, as long as mating is still random the new pool of gametes will randomly unite to form zygotes in equilibrium based on the new allele frequ. most influential when population size is small

101
Q

what is the probability that one allele will go to fixation?

A

the chance of fixation is equal to the allele frequ.

102
Q

what are the effects of random fixation

A

allelic diversity in a population decreases and the population heterozygosity will decrease over time. the effect of GD is greater when population size is small and the faster the heterozygosity will decline
can limit a population’s ability to evolve in changing environment

103
Q

the founder effect

A

when a new population is founded by some colonists, the allele frequ. in this population can differ substantially from those in the parent population

104
Q

population bottleneck

A

a sharp decline in population size that can dramatically change the allele frequ. by initial sampling error and subsequent genetic drift

105
Q

how does the founder effect and bottlenecks effect HW equil.

A

results in dis equilibrium

after one round of random mating it will be restored

106
Q

genetic drift and migration

A

opposite forces, drift increases divergence and F_st but migration decrease
it take little migrations to counter the effects of the drift

107
Q

what are the effects of non-random mating

A

can indirectly effect evolution, but does not change allele frequ.

108
Q

inbreeding

A

mating among closely related, results in deviation from HWE, increase in homozygosity or decrease in heterozygote deficit
affects all loci

109
Q

how does inbreeding effect allele frequ.

A

causes changes in genotype frequ. but not allele frequ.
creates a heterozygote deficit or homozygote excess
not a mechanism for evolution on its own

110
Q

what is inbreeding depression

A

a reduction in the average fitness among individuals within a population due to inbreeding - recessive deleterious alleles will occur in homozygotes more often and decrease overall population fitness

111
Q

outbreeding

A

the opposite of inbreeding - causes heterozygote excess, doesnt change allele frequ. and on its own isnt a mechanism for evolution affects all loci

112
Q

assortative mating

A

positive - individuals with similar phenotypes mate
negative - individuals with dissimilar phenotypes mate
both cause disE with heterozygote deficits in positive and excesses in negative but only at those loci involved in the traits

113
Q

why is small population is a concern for 3 reasons

A
  1. GD will be strong and will reduce heterozygote by randomly fixing alleles removing variation and adaptive potential
  2. drift can overpower natural selection
  3. the probability of mating among close relatives increases in small population sized resulting in inbreeding depression
114
Q

what is the genetic rescue effect

A

an increase in the average population fitness as a result of an increase in genetic diversity, by introducing individuals which mitigates then negative effects of inbreeding and genetic drift

115
Q

what are linkage corridors

A

they connect fragmented and isolated habitats creating a larger habitat where the negative effects of small population size will be less pronounced

116
Q

where does natural selection apply in the life cycle

A

Migration - anywhere
Mutation - during gametogenesis
Genetic drift - gametes b/c only a sample forms zygotes - the sampling event is during the gametes
Inbreeding - the non-random union of gametes
Assortative mating - gametes b/c it is non-random mating
Population bottle neck - can occur any where
Founder effect - any can form the founders of a new population

117
Q

idealisum

A

all natural phenomena are imperfect representation of true essences of an ideal unseen world

118
Q

aristotle

A

further elaborated on idealisum where a deity had creased fixed essences

119
Q

lamarck

A

species changed over time - inheritance of acquired characteristics

120
Q

erasmus

A

grandfather of darwin, proposed that species are modified decedents of earlier forms

121
Q

cuvier

A

catastrophism -earth features had been primarily modeled by catastrophes

122
Q

hutton

A

principle of uniformitarianism - geological processes that we see today are the same as those of the past

123
Q

lyell

A

presented evidence for uniformitarianism ended catastrophism

124
Q

wallace

A

independently arrived to a similar conclusion as darwin

125
Q

Dawin’s evolutionary theory

A
  1. all species, living and extinct, have descended without interruption from one or a few original forms of life
  2. theory of natural selection
126
Q

modern synthesis or neo-darwininan synthesis

A

the mathematical description of the way in which genes behave.

127
Q

a heterozygote deficit can be causes by

A

positive assortative mating, inbreeding, selection (heterozygotes have inferior fitness), migration,
and asexual reproduction.

128
Q

a heterozygote excess can result from

A

selection, outbreeding, negative assortative mating, migration or asexual reproduction