hardy weinberg and fittness

Question 1

hardy winbergy equation

Answer 1

p2+ 2pq + q2 =1

Question 2

p+ q=

Answer 2

1

Question 3

p=

Answer 3

frequency of one allele in the pop. ( dominant)

Question 4

q=

Answer 4

frequency of other alleles (recessive)

Question 5

p2=

Answer 5

proportion of population that is homozygous for the first alleles (RR)

Question 6

2pq

Answer 6

proportion of the population that is heterozygous ( Rr)

Question 7

q2

Answer 7

proportion of the population txt is homozygous for the second allele (rr)

Question 8

H-W equilibrium only applies when

Answer 8

1) discrete generations
2) allele frequency is the same in each sex
3) mendelian segregation occurs
4) population size is large so no genetic drift
5) no gene flow (imm/em)
6) no mutation
7) mating occurs at random
8) no selection

Question 9

in the case of dominant and recessive alleles

Answer 9

you can easily count the number of individuals with the recessive phenotype

• this will give ou the frequency of the double recessive genotype - q2 or dominant (p2.
• with that value you can go on and calc. the frequencies of all other genotypes and alleles

Question 10

large population so no genetic drift

Answer 10

• genetic drift affects small populations

- genetic drift reduced genetic variation

Question 11

no migration or gene flow

Answer 11

migration transfers individuals amongst population

• gene flow transfers alleles amongst population
• can either increase or decrease genetic variation

Question 12

no mutation

Answer 12

• increase genetic variation
• some mutations create dominant alleles, some create recessive or co-dominant alleles
• mutations may be be harmful, neutral or favourable
• effect depends on environment

Question 13

mating occurs at random

Answer 13

• non random mating does not change allele frequencies, but rather hcnages how the alleles are distributed into diploid genotypes
• commone maple of non random mating includes assertive and dissortative mating and inbreeding

Question 14

assortative mating

Answer 14

when individuals mate with those that are similar to themselves - non random
–> leads to an increase in homozygotes

Question 15

disassortative mating

Answer 15

breeding between individuals with dissimilar genotypes- more rare
–> increase in heterozygotes

Question 16

H-W is

Answer 16

of limited use due to fe organisms fulfilling all of these rules

Question 17

Hardy weingberg provides a way of testing whether

Answer 17

a population has evolved or not

-if assumptions are not met the population will evolve

Question 18

if the assumptions are not met a population….

Answer 18

will evolve

Question 19

fitness is used to

Answer 19

measure reproductive success

Question 20

components of fitness

Answer 20

1. survivorship

2. fecundity

Question 21

where is fineness manifested within

Answer 21

phenotype

Question 22

what is phenotype affected by

Answer 22

genes and environment

Question 23

why may fitness of different individuals with the same genotype be different in diff environments

Answer 23

the fitness of a given phenotype can be diff in diff environments
e.g. polar bears white coat acts as camouflage in the north pole and would provide fitness. However if a polar bear was in the jungle its white coat would decrease its fitness

Question 24

(W)

Answer 24

fitness

Question 25

definition of fitness

Answer 25

W is defined as the reproductive success of a genotype relative to the optimum genotype

Question 26

Fitness =

Answer 26

W=1-s

Question 27

s

Answer 27

selection

Question 28

what will be affected if certain alleles affect fitness

Answer 28

the frequency of the alleles will change over time

• alleles with higher fitness become more common–> natural selection

Question 29

alleles with higher fitness will

Answer 29

become more common –> NS

Question 30

methods of measuring fitness

Answer 30

• measure relative survival of the genotypes within a generation. Kettle well;s mark-recapture experiment with he peppered moth is an example.
• measure changes in gene frequencies between generation; we then substitute the measurements in the formula that expresses fitness in terms of gene frequencies in successive generations
• measure deviation from H-W ratios- this is used in estimating fitness in the case off sickle cell anaemia

Question 31

what is measuring deviation from H-W ration used in

Answer 31

measuring fitness in the case of sickle cell anaemia