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Biology Unit 3 > Book Notes- Darwin and other big ideas > Flashcards

Book Notes- Darwin and other big ideas Flashcards

1
Q

Evolution

A

change in genetic composition of populations over time

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2
Q

Change in genetic composition of populations over time

A

Evolution

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3
Q

underlying changes in the genetic makeup of populations drive the

A

origin and extinction of species and fuel the diversification of life

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4
Q

understanding of the mechanisms of evolutionary change

A

evolutionary theory

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5
Q

Evolutionary theory

A

how life diversifies and how species interact

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6
Q

what supports the factual basis of evolution?

A

vast array of geological, morphological, and molecular data

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7
Q

the scientific study of how different organisms function and carry out their lives in nature

A

natural history

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8
Q

Darwin went on a 5 year voyage on the

A

HMS Beagle

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9
Q

Galapagos island observation

A

most animals were endemic (found nowhere else) and most had undergone different and distinctive changes on each island

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10
Q

Darwin’s 3 major propositions

A
  • species change over time
  • divergent species share a common ancestor and have diverged from one another gradually through time (decent with modification)
  • changes in species over time explained by natural selection
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11
Q

Natural selection

A

the differential survival and reproduction of individuals based on variation in their traits

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12
Q

more individuals of most species are born than (blank)

A

survive to reproduce

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13
Q

genetic variation contributes to (blank)

A

phenotypic variation

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14
Q

population evolves when

A

individuals with different genotypes survive and reproduce at different rates

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15
Q

physical expressions of organism’s genes

A

phenotypes

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16
Q

specific form of a character

A

trait

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17
Q

features of phenotype

A

characters

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18
Q

trait at least partly determined by organisms genes

A

heritable

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19
Q

genetic constitution that governs character

A

genotype

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20
Q

different forms of gene exists at locus

A

alleles

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21
Q

particular site on chromosome

A

locus

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22
Q

sum of all copies of all alleles at all loci found in a population

A

gene pool

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23
Q

Evolution can also be defined as

A

changes in the proportions of alleles in a gene pool over time

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24
Q

earth = (blank) years old and life has existed for (blank) of those years

A

4.5 and 3.8

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25
Q

How do scientists date ancient events?

A

geological time scale

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26
Q

Earth’s history is recorded in (blank)

A

rocks

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27
Q

strata

A

oldest layer of rock

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28
Q

stratigraphy

A

certain fossils are always found in younger strata and certain always found in old (old-bottom)

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29
Q

(blank) provide a way to date fossils and rocks

A

Radioisotopes

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30
Q

radioactive isotopes in elements

A

radioisotopes

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31
Q

Radioisotopes

A

decay in predictable patterns over long periods

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32
Q

specific time period- over half of the atoms in a radioisotope decay to become a different, stable isotope

A

half life

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33
Q

formed from materials that existed for varying lengths of time before being weathered, fragmented, and transported, sometimes over long distances to the site of their deposition

A

sedimentary rocks

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34
Q

Radiometric dating of rocks older than 60,000 years requires estimating radioisotope concentrations in (blank)

A

igneous rock

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35
Q

what are the most powerful methods used to construct a geological time scale?

A

radiometric dating of rocks and fossil analysis

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36
Q

relates ages of rocks to patterns in Earth’s magnetism

A

paleomagnetic dating

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37
Q

Hadeon eon

A

time on Earth before life

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38
Q

Archean eon

A

early history of life/ended when photosynthetic organisms 1st appeared

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39
Q

Proterozoic eon

A

prokaryotic life diversified rapidly and first eukaryoes in fossil record

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40
Q

Phanerozoic eon

A

542 mil yr- multicellular eukaryotes rapidly diversified

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41
Q

What 3 eons make up the Precambrian

A

Hadeon, Archean, and Proterozoic

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42
Q

What are the mechanisms of evolutionary change?

A

changes in the genetic makeup of populations over time

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43
Q

a group of individuals of a single species that live and interbreed in a particular geographic area

A

population

44
Q

INDIVIDUALS DO NOT EVOLVE, (BLANK) DO

A

populations

45
Q

4 additional mechanisms of evolution that affect genetic makeup of populations over time

A
  • mutation
  • gene flow
  • genetic drift
  • nonrandom mating
46
Q

mutation generates (blank)

A

genetic variation

47
Q

any change in the nucelotide sequence of an organisms DNA

48
Q

natural selection acts on random variation to produce (blank)

A

adaptation

49
Q

some alleles may become (blank) if environmental conditions change

A

advantageous

50
Q

mutation rate can be low and populations can still contain (blank)

A

large genetic variation

51
Q

sum of the genetic variation in a population

52
Q

proportion of each genotype among the individuals in a pop

A

allele frequency

53
Q

proportion of each genotype among the individuals in pop

A

genotype frequency

54
Q

calculations of frequencies =

A

measurement of evolutionary change

55
Q

selection acting on genetic variation leads to (blank(

A

new phenotypes

56
Q

the purposeful selection of specific phenotypes by humans

A

artificial selection

57
Q

natural selection vs artificial selection

A

traits that helped organisms survive and reproduce vs traits preferred by humans

58
Q

a favored trait that evolves through natural selection

A

adaptation

59
Q

selection for beneficial changes

A

positive selection

60
Q

selection against deleterious changes

A

purifying selection

61
Q

gene flow may change (blank)

A

allele frequencies

62
Q

migration of individuals and movements of gametes between populations

63
Q

example of gene flow

A

neanderthaals and red hair

64
Q

genetic drift may cause large changes in (blank)

A

small populations

65
Q

random changes in allele frequencies from one generation to the next

A

genetic drift

66
Q

genetic drift (blank) in small pop

67
Q

environmental conditions that only a small # of individuals survive

A

population bottleneck

68
Q

example of population bottleneck

A

hunting and habitat destruction, decrease illinois chickens

69
Q

loss of genetic variation in a small population is a problem for (blank)

A

endangered species

70
Q

because of its small size, the colonizing population is unlikely to posses all the alleles found in the gene pool of its source population resulting in decrease in genetic variation

A

founder effect

71
Q

nonrandom mating can change (blank)

A

genotype or allele frequencies

72
Q

individuals of one sex mate preferentially with particular individuals of the opposite sex

A

sexual selection

73
Q

traits that enhance reproduction often reduce (blank)

A

survival chances

74
Q

downfall of sexual selection

A

survival rate reduced

75
Q

example of sexual selection- frogs

A

female prefer low frequency calls because it is a sign of survival

76
Q

example of sexual selection- male african long tailed widowbird

A

females prefer long tails but this means the males can’t fly

77
Q

How do biologists measure evolutionary change?

A

measure evolution by looking at gradual changes in allele and genotype frequencies in populations

78
Q

Evolutionary change can be measured by (blank)

A

allele and genotype frequencies

79
Q

allele frequency (p) =

A

copies of alleles in population/ total # of copies of all alleles in pop

80
Q

p + q =

81
Q

if there is only one allele at a given locus in a population, frequency = (blank) and the population is (blank) meaning the allele is (blank)

A

1, monomorphic, fixed

82
Q

frequencies of the different alleles at each locus and the frequencies of different genotypes in a population describe population

A

genetic structure

83
Q

Evolution will occur unless certain (blank) exist

A

restrictive conditions

84
Q

model in which allele frequencies do not change across generations, and genotype frequencies can be predicted from allele frequencies

A

Hardy-Weinberg equilibrium

85
Q

several conditions of hardy-weinberg

A
  • no mutation
  • no selection among genotypes
  • no gene flow
  • population size is infinite
  • mating is random
86
Q

2 consequences of Hardy-Weinberg

A
  • frequencies of alleles at a locus remain constant from generation to generation (no evolutionary change)
  • genotypes occur at certain frequencies (p2+2pq+q2)
87
Q

Deviations from Hardy-Weinberg equilibrium show that

A

evolution is occuring

88
Q

Hardy Weinberg is useful for

A

predicting the approx genotype frequencies of a pop from its allele frequencies

89
Q

Hardy Weinberg model allows biologists to

A

evaluate which mechanisms of evolution are acting on a particular population

90
Q

Natrual selection acts directly on (blank)

A

phenotypes

91
Q

Reproductive contribution of a phenotype to subsequent generations relative to the contributions of other phenotypes

92
Q

Changes in #s of offspring are responsible for increases and decreases in the (blank) of a population

93
Q

changes in the (blank) of different phenotypes in a population will lead to changes in allele frequencies from one generation to the next

A

relative success

94
Q

(blank) of a phenotype is determined by the relative rates of survival and reproduction of individuals with that phenotype

95
Q

natural selection can (blank) or (blank) populations

A

change or stabilize

96
Q

show continuous variation

A

quantitative traits

97
Q

preserves the average characteristics of a population by favoring average individuals

A

stabilizing selection

98
Q

changes the characteristics of a population by favoring individuals that vary in 1 direction from the mean of the population

A

directional selection

99
Q

changes the characteristics of a population by favoring individuals that vary in both directions from mean of population

A

disruptive selection

100
Q

stabilizing selection

A

reduces variation in pop, but does not change mean

101
Q

example of stabilizing selection

A

human birth weight

102
Q

directional selection

A

individuals at 1 extreme, shift avg value

103
Q

example of directional selection

A

texas longhorns

104
Q

disruptive selection

A

individuals at opposite extremes contribute more offspring than mean (increases variation)

105
Q

example of disruptive selection

A

West African Finch Bill size

Biology Unit 3 (5 decks)

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