Evolution Chap 19

Question 1

population

Answer 1

all individuals in one area at one time that may interbreed and exchange genes

Question 2

population genetics

Answer 2

genes change through evolution by genetic vatriation

Question 3

phenotypic variation

Answer 3

varied gene expression in the same population, single or multiple genes

Question 4

natural selection

Answer 4

random mutations from non random selection. can be adaptive or maladaptive traits

Question 5

genetic drift

Answer 5

change alone shifts phenotype
becomes more common over generations

Question 6

gene flow

Answer 6

new alleles enter population
new phenotypes in new generation

Question 7

gene variability

Answer 7

whole gene level variation
proportion of zygosity (ex. fruit fly with 14% heterozygous/84% homozygous)

Question 8

nucleotide variability

Answer 8

molecular variability in DNA
most variations do not mean change in phenotype
however, one change can be significant

Question 9

non-heritable variation

Answer 9

acquired traits cannot be passed

Question 10

neutral variation

Answer 10

no observed affect/advantage
only passed in germ cells

Question 11

gene number/position

Answer 11

translocations of one gene – may accumulate over time
1 gene to many genes

Question 12

rapid repro

Answer 12

eukaryotes have low mutation rates
prokaryotes have high likelihood for mutation

Question 13

sexual repro

Answer 13

shuffling of alleles
crossing over (prophase 1)
independent assortment (metaphase 1)

Question 14

microevolution

Answer 14

small scale evolution (moths in industrial revolution)

Question 15

hardy Weinberg equation

Answer 15

p^2 + 2pq + q^2 = 1.0

Question 16

HW is true if …

Answer 16

1. no mutations
2. no migrations
3. large gene pool
4. random mating
5. no selection

Question 17

genetic drift

Answer 17

change in alleles by change
from random event
change not linked w/ evolution

Question 18

founder effect

Answer 18

few individuals leave the population so the gene pool is small to start so more likely carryover of recessive traits

Question 19

bottleneck effect

Answer 19

small fragmented populations so limited genetic diversity
gene pool is restricted so adaptability is restricted

Question 20

consequences of genetic drift

Answer 20

1. significant in spall populations however observed in all populations
2. allele frequency may change at random
3. loss of genetic variation within population
4. harmful alleles may become fixed

Question 21

directional selection

Answer 21

changes one direction or another compared to the previous avg

Question 22

disruptive selection

Answer 22

only the extremes are selected (2+ extremes)

Question 23

stabilizing

Answer 23

favoring the average
more likely to be carried over

Question 24

sexual selections

Answer 24

adaptive changes to males and females
males–> increase ability to compete
females –> preferential selection of mate

Question 25

sexual dimorphism

Answer 25

distinct differences between sexes
size and color are most common

Question 26

intersexual selection

Answer 26

individuals w/in sex compete
males patrol/protect territory
“psychological” effect to prevent physical altercation

Question 27

intersexual selection

Answer 27

mate choice is noticeable
chooses individuals w/ better genes
ex. colorful bird mating displays

Question 28

balancing selection

Answer 28

maintenance of undesirable alleles in a population
dependent on frequencies
prey species defend against majority so natural fluctuation exists as a result

Question 29

heterozygous advantage

Answer 29

heterozygotes have better fitness
defined by genotype
effects depends on phenotype of heterozygote (sickle cells traits)

Question 30

HW equation

Answer 30

p^2 + 2pq + q^2 = 1

Question 31

q =

Answer 31

recessive allele

Question 32

p=

Answer 32

dominant allele

Question 33

p^2

Answer 33

HoD

Question 34

q^2

Answer 34

HoR

Question 35

2pq

Answer 35

HetD