Evolution of Population

Question 1

adaptation

Answer 1

heritable trait or behavior in an organism that aids in its survival and reproduction in its present environment

Question 2

adaptive evolution

Answer 2

increase in frequency of beneficial alleles and decrease in deleterious alleles due to selection

Question 3

allele frequency

Answer 3

rate at which a specific allele appears within a population (aka gene frequency)

Question 4

artificial selection

Answer 4

the process by which humans choose individual organisms with certain phenotypic trait values for breeding

Question 5

assortative mating

Answer 5

when individuals tend to mate with those who are phenotypically similar to themselves

Question 6

beneficial mutation

Answer 6

a type of mutation that has a positive effect on an organism

Question 7

bottleneck effect

Answer 7

magnification of genetic drift as a result of natural events or catastrophes

Question 8

convergent evolution

Answer 8

process by which groups of organisms independently evolve to similar forms

Question 9

deleterious mutation

Answer 9

genetic alteration that increases an individual’s susceptibility or predisposition to a certain disease or disorder

Question 10

directional selection

Answer 10

selection that favors phenotypes at one end of the spectrum of existing variation

Question 11

diversifying (disruptive) selection

Answer 11

selection that favors two or more distinct phenotypes

Question 12

divergent evolution

Answer 12

process by which groups of organisms evolve in diverse directions from a common point

Question 13

evolutionary (Darwinian) fitness

Answer 13

individual’s ability to survive and reproduce

Question 14

fixation (fixed)

Answer 14

the preservation of biological tissues from decay due to autolysis or putrefaction

Question 15

founder effect

Answer 15

event that initiates an allele frequency change in part of the population, which is not typical of the original population

Question 16

gene flow

Answer 16

flow of alleles in and out of a population due to the individual or gamete migration

Question 17

gene pool

Answer 17

all the alleles that the individuals in the population carry

Question 18

genetic drift

Answer 18

effect of change on a population’s gene pool

Question 19

genetic variabillity

Answer 19

diversity of alleles and genotypes in a population

Question 20

Hardy-Weinberg Equilibrium

Answer 20

allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences

Question 21

Heterozygote advantage

Answer 21

the case in which the heterozygous genotype has a higher relative fitness than either the homozygous dominant or homozygous recessive genotype

Question 22

inbreeding

Answer 22

mating of closely related individuals

Question 23

inbreeding depression

Answer 23

increase in abnormalities and disease in inbreeding populations

Question 24

migration

Answer 24

a pattern of behavior in which animals travel from one habitat to another in search of food, better conditions, or reproductive needs

Question 25

modern synthesis

Answer 25

overarching evolutionary paradigm that took shape by the 1940s and scientists generally accept today

Question 26

negative selection

Answer 26

the selective removal of alleles that are deleterious

Question 27

neutral mutation

Answer 27

mutation that neither benefits nor harms the individual

Question 28

nonrandom mating

Answer 28

changes in a population’s gene pool due to mate choice or other forces that cause individuals to mate with certain phenotypes more than others

Question 29

population genetics

Answer 29

study of how selective forces change the allele frequencies in a population over time

Question 30

positive selection

Answer 30

the process by which new advantageous genetic variants sweep a population

Question 31

relative fitness

Answer 31

individual’s ability to survive and reproduce relative to the rest of the population

Question 32

selection pressure

Answer 32

environmental factor that causes one phenotype to be better than another

Question 33

sexual dimorphism

Answer 33

phenotypic difference between a population’s males and females

Question 34

stabilizing selection

Answer 34

selection that favors average phenotypes

Question 35

variation

Answer 35

genetic differences among individuals in a population