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Flashcards in CH. 4 Deck (22):
1

Population Genetics*

The study of factors affecting gene and genotypic frequencies in a population.

2

Gene or Allelic Frequency*

The relative frequency of a particular allele in a pop. Designated by p and q

3

Genotypic frequency*

The relative frequency of a particular one-locus genotype in a pop. Designated by P, Q, and H

4

p

The frequency of the dominant allele

5

q

the frequency of the recessive allele

6

The effect of selection

Is to increase the gene frequency of favorable alleles. Better set of genes+ better breeding values

7

Fixation*

The point at which a particular allele becomes the only allele in the pop.
Ex. Purebred black angus

8

Mating systems

"sets of rules" for determining which selected males is bred to which selected females

9

Inbreeding

the mating of relatives. increases the frequency of homozygosity but decreases the frequency of heterozygosity.

10

Outbreeding

the mating of unrelated individuals. Increases the frequency of heterozygousity and decreases the frequences of homozygoisity

11

half-sibs*

half brothers and/or sisters

12

Common ancestor*

an ancestor common to more than one individual

13

pedigree relationship*

relationship between animals due to kinship

14

Arrow diagram*

A form of pedigree depicting schematically the flow of genes from ancestors to descendants

15

F1*

Referring to the first generation of crosses between two unrelated (though not necessarily purebred) populations.

16

F2*

Referring to the generation of crosses produced by mating F1 (first-cross) individuals among themselves

17

Hardy-Weinburg Equilibrium*

A state of constant gene and genotypic frequencies occurring in a pop in the absence of forces that change those frequencies.

18

H-W Equation

p^2+2pg+q^2=1
P=p^2
H=2pq
Q=q^2

19

Assumptions for H-W Equilibrium

organisms are diploid
Only sexual reproduction occurs
Generations are non-overlapping
Mating is random
Pop size is infinitely large
Allele frequencies are equal in the sexes
There is no migration, mutation or selection

20

Mutation*

Process that alters DNA to create new alleles

21

Migration *

The movement of individuals into or out of a pop.

22

Random Drift*

Change in gene frequencies in small pops due purely to chance