Key Terms for Exam II, Practice questions, Old quiz questions Flashcards Preview

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Flashcards in Key Terms for Exam II, Practice questions, Old quiz questions Deck (66):
1

Species exist when they are _____ from one another because of a lack of _____.

Genetically isolated from one another because of a lack of gene flow.

2

Divergence in traits such as genitalia shape prevents fertilization. What specific type of pre-zygotic isolation is this known as?

Mechanical isolation

3

When there is high allelic diversity within a population, is there a good or bad chance of evolution?

Good chance

4

 Dispersal and vicariance result in _____ speciation.

Allopatric speciation

5

The _____ looks at genetic divergence as well as morphological traits.

Phylogenetic species

6

The _____ considers evolutionary independence due to reproductive isolation.

Biological species concept

7

 The _____ is the primary way in which fossils are assigned to species

Morphospecies concept

8

Allele frequencies do not change very much due to _____. And in no case will an allele be lost.

Genetic drift

9

Allelic frequency increases over generations. This is due to what?

Selection

10

Allelic frequency decreases over time and eventually the allele is lost. This is due to?

Deleterious mutation

11

Mutations that affect cells in the body

Somatic mutations

12

Mutations that affect games and can be passed from parents to offspring

Germ-line mutations

13

A trait for which multiple, discrete phenotypes can arise from a single genotype depending on environmental circumstances

Polyphenic trait

14

A signaling molecule that flows between nearby cells and acts directly to alter expression of target genes

Morphogen

15

Measurable phenotypes that vary among individuals over a given range to produce a continuous distribution of phenotypes

Quantitative traits

16

A type of genetic drift describing the loss of allelic variation that accompanies formation of a new population

Founder effect

17

Occurs when the effects of an allele at one locus are modified by alleles at one or more other loci

Epistasis

18

Selection that favors more than one allele. It acts to maintain genetic diversity

Balancing selection

19

This is when rare genotypes have higher fitness than common genotypes. This process can maintain genetic variation in a population.

Negative frequency-dependent selection

20

An allele that yields twice the phenotypic effect when two copies are present at a given locus than when only a single copy is present is known as...

An additive allele

21

Natural selection is ineffective in a _____ population and effective in _____ ones.

Small - ineffective

Large - effective

22

Based on the options above, _____ most specifically defines when two rival males 
compete.

Interspecific conflict

23

Based on the options above, _____ more generally defines when two rival males 
compete.

 

Intraspecific conflict

24

Sharp-shooters have a morphological trait known as a _____.

 

Bacteriome

25

 The sharp-shooter example most correctly represents an example of _____.

 

Endosymbiosis

26

_____ is when species interact antagonistically in a way that results in each species 
exerting reciprocal directional selection on the other.

 

Coevolutionary escalation/arms race

27

 A relationship involving two species in which one species benefits but the other suffers no loss of fitness is 
known as _____.

Positive/neutral commensalism

28

One of several alternative forms of DNA sequence of same locus

Allele

29

A form of cell division that occurs only in eukaryotes. # of chromosomes cut in half

Meiosis

30

Exchange of genetic material between paired chromosomes during meiosis

Genetic recombination

31

Alleles that produce the same phenotype whether they are paired with an identical allele or a different allele

Dominant allele

32

Alleles that produce their characteristic phenotype only when they are paired with an identical allele

Recessive allele

33

Changes in the phenotype produced by a single genotype in different environments

Phenotypic plasticity

34

The study of distribution of alleles within populations and the mechanisms that cause allelic frequencies to change over time

Population genetics

35

The specific locus of a gene or piece of DNA sequence on a chromosome

Genetic locus

36

This theorum proves that in absence of genetic drift, mutation, selection, migration, allele frequencies at a genetic locus will not change from one generation to the next

Hardy-Weinburg equilibrium

37

An allele becomes _____ in a population when all of the alternative alleles have disappeared

Fixed

38

The success of an organism at surviving and reproducing, contributing offspring to future generations

Fitness

39

Success of the genotype at producing new individuals standardized by the success of other genotypes in the population

Relative fitness

40

Difference between average fitness of individuals bearing the allele and average fitness of population as a whole

Average excess of fitness

41

Condition when a mutation in a single gene affects the expression of many different phenotypic traits

Pleiotropy

42

Selection that decreases the frequency of alleles within a population

Negative selection

43

Selection that increases the frequency of alleles within a population

Positive selection

44

The probability that the two alleles at any locus in an individual will be identical by descent

Inbreeding coefficient

45

A reduction in the average fitness of inbred individuals relative to that of outbred individuals

Inbreeding depression

46

A group of spatially separated populations of the same species that interact at some level

Metapopulation

47

Species are metapopulations of organisms that exchange alleles frequently enough that they comprise the same gene pool and therefore same evolutionary lineage

General lineage species concept

48

An aspect of the environment, genetics, behavior, physiology, or ecology of a species that reduces or impedes gene flow from individuals of other species

Isolation barrier

49

Evolutionary process by which new species arise

Speciation

50

Occurs when populations are in separate, non over-lapping geographic areas

Allopatric

51

Occurs when populations are in same geographic area

Sympatry

52

Occurs when reproductive barriers prevent or strongly limit reproduction between populations

Reproductive isolation

53

Occurs when sperm or pollen from one species fails to penetrate and fertilize the egg of another species

Gametic incompatibility

54

Divergence in traits between population that prevents fertilization

Prezygotic isolation

55

Hybrid offspring that are sterile/infertile 

Postzygotic isolation

56

Breeding at different times pf the year

Temporal isolation

57

Different calls/mating dances

Behavioral isolation

58

Reciprocal evolutionary change between interacting species, driven by natural selection

Coevolution

59

Selection that occurs in two species, due to their interactions with one another

Reciprocal selection

60

A theory that proposes that the geographic structure of populations is central to the dynamics of coevolution

Geographic mosaic theory of coevolution

61

Occurs when several harmful/distasteful species resemble each other in appearance, facilitating learned avoidance of predators

Mullerian mimicry

62

Occurs when harmless species resemble harmful/distasteful species, deriving protection from predators in the process

Batesian mimicry

63

An increase in genetic diversity caused by the heterogeneity of coevolutionary processes across the range of ecological partners

Diversifying coevolution

64

Mutualistic organisms that live within the body or cells of another organism

Endosymbionts

65

An RNA virus that uses an enzyme called reverse transcriptase to become part of the host cells' DNA

Retrovirus

66