Final - Lecture 3

Question 1

Impact of constant N over generations on inbreeding?

Answer 1

Not important

- if it changes - recalculate

Question 2

Impact of constant proportion of males and females on inbreeding?

Answer 2

Not important

• if it changes - recalculate
• wide increase/decrease = not good

Question 3

Impact of closed population on inbreeding?

Answer 3

Closed = calculation is valid
Open = calculation means nothing

Question 4

Impact random mating has on inbreeding?

Answer 4

A lot of inbreeding can be avoided by careful management

Question 5

Impact of equal progeny on inbreeding?

Answer 5

Violated quite frequently

- just go back to N and ratio of females and males and recalculate

Question 6

Impact of discrete generations on inbreeding?

Answer 6

• Population breeds once and that’s it
• both important/unimportant
• exception for species that reproduce and die (e.g. coho salmon)

Question 7

The engine that powers selection?

Answer 7

Genetic variability

Question 8

Why are we interested in additive genetic variation?

Answer 8

Only thing that gets passed onto offspring

Question 9

Genetic variability magnitude influenced by?

Answer 9

• range of allele frequencies of loci involved

- range of associated phenotypic expression for these loci

Question 10

What is the amount of variability observed equal to?

Answer 10

The range of specific phenotypic loci expressed

Question 11

When is heterozygosity maxed out?

Answer 11

when p=q=0.5

- maximum variability when we have an abundance of both alleles

Question 12

Degree to which heterozygotes are expressing dominance?

Answer 12

A lot of genetic variance = not a lot of dominance (mutually exclusive)
- high heritability = high additive genetic variation = low dominance

Question 13

Alternative expression

Answer 13

codes for different proteins

Question 14

Tandem repeats

Answer 14

alters amount/rate of expression
- stutters in DNA –> change rate at which DNA is expressed; variability varies depending on the amount of expression (e.g. evolution of bull terrier skull)

Question 15

What is responsible for black/brown coat in dogs?

Answer 15

Eumelanin

Question 16

What is responsible for yellow/red coat?

Answer 16

Pheomelanin

Question 17

C-BARQ tested what?

Answer 17

Show vs. field and black vs. yellow

Question 18

Runx-2 is responsable for?

Answer 18

Osteroblast differentiation

- associated with bull terrier skull

Question 19

What happens to additive genetic variation and dominance when heterozygosity decreases due to inbreeding?

Answer 19

They decrease

Question 20

Inbreeding depression

Answer 20

After some arbitrary number of generations, inbreeding has accumulated in an inbred line

Question 21

If Aa falls directly between AA and aa, dominance is equal to?

Answer 21

0

Question 22

What is considered the eraser of inbreeding?

Answer 22

cross-breeding

Question 23

Cross breeding is also called

Answer 23

Out-crossing

- seeking as much genetic variation with 2 individuals you are trying to breed

Question 24

What is cross breeding?

Answer 24

Crossing two unrelated (inbred) lines

- creates heterosis

Question 25

What is heterosis?

Answer 25

Amount of the crossbred mean that exceeds the average of the line means

Question 26

Suppose f(A) –> 1 and f(a) –> 0, where does additive genetic variation go?

Answer 26

0

Question 27

Finite Locus Model

Answer 27

Small number of loci with large effects on the phenotype

• selection reaches plateau when f(A) = 1
• selection reduces genetic additive variation = Bulmer effect
• better the progress = less variation
• qualitative traits

Question 28

Infinitesimal Model

Answer 28

Many loci with small effects on the phenotype

• selection continues forever
• some genetic variation remains
• quantitative traits