Exam 1 Flashcards
Genotype
The Genetic Make-up of an individual
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
Performance Testing
Systematic measurement of phenotype in a population
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
Polygenic
A trait affected by many genes, no single gene having an overriding influence
Threshold
A polygenic trait in which phenotypes are expressed in categories
Testing mating
A mating designed to reveal the genotype of an individual for a small number of loci
Selection
A process which determines which individuals become parents
Crossbreeding
Having parents of different breeds or breed combinations
F1
First generation of crosses between two unrelated populations
Culling
The process that determines which parents will no longer remain parents
Segregation
The separation of paired genes during germ cell formation
Breeding value
The value of an individual as a genetic parent
Heritability
A measure of the strength of a relationship between breeding values and phenotypic values for a trait in a population
Germ Plasm
Genetic Material in the form of live animals, semen, or embryos
allele
an alternative form of a gene
progeny
info on the genotype or performance of descendants of an individual
Breeding true
In simple inheritance, when two parents w/a given phenotype always produce offspring w/that same phenotype
Accuracy
A measure of the strength of the relationship between true values and their predictions
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
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
Genotypic frequency of P
AA
Homozygous Recessive
aa
Genotypic Frequency= 2pq
Aa
Heterozygous
Aa
Genotypic Frequency = q^2
aa
Frequency increased in Crossbreeding
Aa
In complete dominance, which genotype would have a different phenotype than the other two
aa
In overdominance, which genotype usually expresses a phenotype that has the most breeding value.
Aa
In complete dominance, which genotype would most likely to be lethal
aa
In partial dominance which genotype would be selected despite the presence of an undesirable allele
Aa
Avg. Daily gain in livestock
polygenic
Most lethal or semi-lethal alleles
simply-inherited
Threshold traits
polygenic
Tend to be qualitative
simply-inherited
Presence of horns in cattle
simply-inherited
Which sex-related trait is involved with scurs in cattle?
influence
which sex-related trait are antlers in deer?
limited
Which sex-related trait leads to calico cats
Linked
Lyonization causes differences
linked
Which inheritance is effected by hemizygosity
Sex-related
List Mendel’s Laws of inheritance
Law of Segregation, Law of independent Assortment, Law of Dominance
WHich has the ZW Sex Chromosome
Hen (female in birds)
Which is hemizygous?
Bull
Which is the “default: pathway in sexual differetiation?
female
Which undergoes Lyonization
XX
Data providing info on the genotype or performance of ancestors of an individual
pedigree
T/F: Segregation and Independent Assortment occur during Meiosis
true
T/F: Dominant Genes are more common than recessive genes
False
Heritability of Reproductive or Fertility Traits in most animals
LOw
The frequency of a specific allele in a population
Gene
Increases homozygosity
inbreeding
List the 4 forces that change H-W E
Selection, Mutation Migration, random drift
What are the 2 processes used in Artificial Selection during animal breeding
culling and replacement selection
What mating system increases heterozygosity?
crossbreeding
Give two examples of physical environment
temperature and humidity
two exs. of fixed resources/management
size of farm and number of animals
two exs. of economics
cost of inputs and cost of outputs
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.
What is the H-W Equation?
p^2+2pq+q^2=1
WHat is the Jost Paradign?
Chromosomal Sex leads to Gonadal Sex. Gonadal Sex leads to Phenotypic Sex
Define Sex-linked
The pattern of inheritance for genes located on sec chromosomes (X or Y) ex. calico cats
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
Simply Inherited
A trait that only has one or a few genes that cause the trait. ex. coat color in dogs
What is population Genetics?
The study of factors affecting gene and genotypic frequencies in a population
