Exam 4 pt 2

Question 1

bottleneck

Answer 1

when a population undergoes a drastic reduction in size

Question 2

regression

Answer 2

linear relationship between 2 variables

Question 3

sympatric

Answer 3

speciation arises in the absence of any geographic barrier to gene flow

Question 4

narrow sense heritability

Answer 4

proportion of phenotypic variance that is due to additive genetic variance

Question 5

inbreeding

Answer 5

preferential mating between related individuals

Question 6

positive assortative mating

Answer 6

tendency for like individuals to mate

Question 7

founder effect

Answer 7

establishment of a population by a small number of individuals

Question 8

variance

Answer 8

indicates the variability of a group of measurements

Question 9

allopatric

Answer 9

speciation is initiated when a geographic barrier splits a population intro

Question 10

broad sense heritability

Answer 10

proportion of phenotypic variance that is due to genetic variance

Question 11

quantitative

Answer 11

a trait that is continously variable over some measure

Question 12

qualitative

Answer 12

a trait with only a few distinct phenotypic classes

Question 13

correlation

Answer 13

the strength of association between two measurements

Question 14

mean

Answer 14

provides information about the center of a distribution

Question 15

why correlation does not equal causation

Answer 15

just because two events are correlated or have a strong association does not mean one causes the other

Question 16

if you have (or already had) children, what would be your best estimate of their adult height before they are even born

Answer 16

the mean of both parents heights

Question 17

assuming a trait has a high narrow sense heritability, which relationship would you expect to be more similar in phenotype for the traits

Answer 17

full siblings

Question 18

bristle number in drosophilia is a highly heritable trait with h^2 = .52 if the average bristle number in the parental population was 35.3 and one selected flies to produce the next generation that had mean bristle number of 40.6 what is the selection differential

Answer 18

5.3

Question 19

traits that have a moderate to high heritability respond to selection however, one cannot continue to select for a trait and realize a response indefinitely what are 2 reasons why a trait may cease to respond to selection

Answer 19

organism reaches maximum genetic potential physiologically and no more alleles/diversity to select for

Question 20

why hertiability cannot be calculated for an individual, and heritability has no meaning for a specific individual

Answer 20

heritability is calculated using statistics for a population in a specific enviornment so you need a large sample size to calculate it, results only apply to the population

Question 21

what is the relationship between rainfall and temperature

Answer 21

more rainfall when the temperature is high

Question 22

why does environmental impact on genetics greater with plants than animals

Answer 22

because plants cant move from their envornments

Question 23

in a herd of dairy cattle, milk yield and the percentage of butterfat exhibit a genetic correlation of -.38 if greater milk yield is selceted in this herd, what will be the effect on the percentage of butterfat?

Answer 23

the percentage butterfat will decrease

Question 24

a particular location on a chromosome, say chromosome 1 position 120,256,947 bp, has three alleles segregating in the population, if the frequency of the A allele is .20 and the frequency of the C allele is .10 what is the frequency of the T allele

Answer 24

.70

Question 25

5 assumptions for a population in HWE

Answer 25

no mutation, no migration, no natural selection, no genetic drift, no non random mating

Question 26

if these assumptions are met, what two predictions can be made in a population in equilibrium

Answer 26

allelic frequencies will not change and genotypic frequencies will reach equilibrium

Question 27

does inbreeding have an affect on allelic frequencies

Answer 27

no

Question 28

what effect does inbreeding have on genotype frequencies

Answer 28

selects towards more homozygous genotypes

Question 29

why does inbreeding not have an affect on allelic frequencies

Answer 29

breeding between related individuals doesnt cause alleles to be lost or gained

Question 30

sample error arises when gametes limits to produce progeny the variance in allelic frequency at a locus is determined by the frequency of the alleles at the locus what loci will have the largest variance in allele frequency

Answer 30

locus 2 where p = .50

Question 31

what does it mean for a population to meet HWE

Answer 31

being in HWE means allele frequencies do not change and if they dont evolution can not occur

Question 32

what is the predominant mechanism distinguishing species

Answer 32

reproductive isolation

Question 33

what are two types of pre zygotic mechanisms that lead to speciation

Answer 33

gametic isolation and behavioral isolation

Question 34

when a population is in mutational equilibrium what is true

Answer 34

the number of forward mutations is equal to the number of reverse mutations