LECTURE 17 (Pop genetics 2)

Question 1

what are the 4 forces that cause deviations from HWE?

Answer 1

• mutation: forward A–>a or backwards a–A
• drift
• migration
• selection

Question 2

how is the rate of mutation shown?

Answer 2

u

Question 3

if there’s a mutation, how do we calculate the frequency in the next generation?

Answer 3

p’=p-up

Question 4

how do we calculate the frequency in any generation when there’s mutation?

Answer 4

Pt= px e^- u t

Question 5

what’s selection?

Answer 5

it’s a force that acts independently on genes
it happens when two individuals vary in their relative fitness
only way by which adaptations occur

Question 6

what are the 4 components of natural selection that affect sexual diploids?

Answer 6

• sexual selection (competition)
• viability selection (some offspring are more likely to survive to adulthood)
• gametic selection ( some gametes segregate more easily)
• fecundity selection ( the amount of offspring females can carry)

Question 7

what’s fitness? absolute? relative?

Answer 7

contribution to the phenotype/genotype to the next generation
absolute: the number of viable offspring a phenotype/genotype(individual) leaves –> W
relative fitness: fitness of an individual relative to other individuals (usually the most fit)