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Flashcards in Exam 1 Deck (65):
1

Genotype

The Genetic Make-up of an individual

2

Interaction

A dependent relationship among components of a system in which the effects of any one component depends on the other components present in the system

3

Performance Testing

Systematic measurement of phenotype in a population

4

Epistasis

An interaction among genes at different loci such that the expression of genes at one locus depends on the alleles present at one or more other loci

5

Polygenic

A trait affected by many genes, no single gene having an overriding influence

6

Threshold

A polygenic trait in which phenotypes are expressed in categories

7

Testing mating

A mating designed to reveal the genotype of an individual for a small number of loci

8

Selection

A process which determines which individuals become parents

9

Crossbreeding

Having parents of different breeds or breed combinations

10

F1

First generation of crosses between two unrelated populations

11

Culling

The process that determines which parents will no longer remain parents

12

Segregation

The separation of paired genes during germ cell formation

13

Breeding value

The value of an individual as a genetic parent

14

Heritability

A measure of the strength of a relationship between breeding values and phenotypic values for a trait in a population

15

Germ Plasm

Genetic Material in the form of live animals, semen, or embryos

16

allele

an alternative form of a gene

17

progeny

info on the genotype or performance of descendants of an individual

18

Breeding true

In simple inheritance, when two parents w/a given phenotype always produce offspring w/that same phenotype

19

Accuracy

A measure of the strength of the relationship between true values and their predictions

20

Fixation

The point at which a particular allele becomes the only allele at its locus in a population and frequency of the allele becomes one

21

Heterosis

A dependent relationship among components of a system in which the effects of any one component depends on the other components present in the system

22

Genotypic frequency of P

AA

23

Homozygous Recessive

aa

24

Genotypic Frequency= 2pq

Aa

25

Heterozygous

Aa

26

Genotypic Frequency = q^2

aa

27

Frequency increased in Crossbreeding

Aa

28

In complete dominance, which genotype would have a different phenotype than the other two

aa

29

In overdominance, which genotype usually expresses a phenotype that has the most breeding value.

Aa

30

In complete dominance, which genotype would most likely to be lethal

aa

31

In partial dominance which genotype would be selected despite the presence of an undesirable allele

Aa

32

Avg. Daily gain in livestock

polygenic

33

Most lethal or semi-lethal alleles

simply-inherited

34

Threshold traits

polygenic

35

Tend to be qualitative

simply-inherited

36

Presence of horns in cattle

simply-inherited

37

Which sex-related trait is involved with scurs in cattle?

influence

38

which sex-related trait are antlers in deer?

limited

39

Which sex-related trait leads to calico cats

Linked

40

Lyonization causes differences

linked

41

Which inheritance is effected by hemizygosity

Sex-related

42

List Mendel's Laws of inheritance

Law of Segregation, Law of independent Assortment, Law of Dominance

43

WHich has the ZW Sex Chromosome

Hen (female in birds)

44

Which is hemizygous?

Bull

45

Which is the "default: pathway in sexual differetiation?

female

46

Which undergoes Lyonization

XX

47

Data providing info on the genotype or performance of ancestors of an individual

pedigree

48

T/F: Segregation and Independent Assortment occur during Meiosis

true

49

T/F: Dominant Genes are more common than recessive genes

False

50

Heritability of Reproductive or Fertility Traits in most animals

LOw

51

The frequency of a specific allele in a population

Gene

52

Increases homozygosity

inbreeding

53

List the 4 forces that change H-W E

Selection, Mutation Migration, random drift

54

What are the 2 processes used in Artificial Selection during animal breeding

culling and replacement selection

55

What mating system increases heterozygosity?

crossbreeding

56

Give two examples of physical environment

temperature and humidity

57

two exs. of fixed resources/management

size of farm and number of animals

58

two exs. of economics

cost of inputs and cost of outputs

59

Describe an ex. of phenotypic selection

Phenotypic selection is selecting based on physical aspects of an animal to breed. you dont know the genptype so your basing your selection off of what you see. Ex. mating a polled cow w/another polled bull expecting a polled calf even though you dont know the genes.

60

What is the H-W Equation?

p^2+2pq+q^2=1

61

WHat is the Jost Paradign?

Chromosomal Sex leads to Gonadal Sex. Gonadal Sex leads to Phenotypic Sex

62

Define Sex-linked

The pattern of inheritance for genes located on sec chromosomes (X or Y) ex. calico cats

63

Sex-limited

A pattern of inheritance in which the phenotypic expression is limited to one sex (gender). But the other gender still has alleles for trait. ex. boobs

64

Simply Inherited

A trait that only has one or a few genes that cause the trait. ex. coat color in dogs

65

What is population Genetics?

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