exam 3 ppt 7

Question 1

definition of gene pool

Answer 1

all the alleles present in all individuals in a species

Question 2

what does genetic variation in a population refer to?

Answer 2

refers to multiple alleles within a gene pool

Question 3

in HWE formula, what does pq represent?

Answer 3

represents heterozygotes

Question 4

is “populations must select their mates” an assumption of HWE?

Answer 4

no

Question 5

what genotype is represented by p^2?

Answer 5

homozygous dominant

Question 6

what genotype is represented by 2pq?

Answer 6

heterozygous

Question 7

what genotype is represented by q^2?

Answer 7

homozygous recessive

Question 8

what does HWE describe?

Answer 8

HWE describes situations in which allele and genotype frequencies do not change

Question 9

5 assumptions in HWE

Answer 9

1) individuals must mate at random, 2) no natural selection, 3) no genetic drift, 4) no gene flow, 5) no mutation

Question 10

what does the assumption mean in HWE that there is no natural selection?

Answer 10

there can be no differences in the survival and reproductive success of individuals

Question 11

what does the assumption mean in HWE that there is no genetic drift?

Answer 11

the population must be sufficiently large to prevent sampling errors

Question 12

what does the assumption mean in HWE that there is no gene flow?

Answer 12

populations must not be added to or subtracted from by migration

Question 13

what does the assumption mean in HWE that there is no mutation?

Answer 13

no new alleles can be introduced into the gene pool

Question 14

if a population is NOT in HWE, this tells us…

Answer 14

a population is evolving

Question 15

what is HWE a starting point for?

Answer 15

a starting point to determine if the population is: undergoing natural selection, migrating, experiencing genetic drift, experiencing new mutations, not mating randomly

Question 16

what happens to allele frequencies if the population is not evolving?

Answer 16

allele frequencies stay the same from one generation to the next

Question 17

if you are not told to assume HWE, can you use p^2 + 2pq + q^2 =1 to work backwards?

Answer 17

no

Question 18

how do we know if differences are different enough to cause evolution?

Answer 18

using chi square test

Question 19

definition of chi squared

Answer 19

test of goodness-of-fit of null hypothesis that observed and expected frequencies are the same

Question 20

degrees of freedom =

Answer 20

n-1, where n is the number of possible dats points

Question 21

equation for chi square test

Answer 21

(observed - expected)^2 / expected

Question 22

definition of p-values

Answer 22

how likely it is due to random chance (0.05 and less= statistically significant)

Question 23

P > 0.05=

Answer 23

observed and expected values are not significantly different