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A ____ is an observable or measurable characteristic of an individual
trait
black faced sheep breeds share similar genotypes for meat traits and therefore are considered to be of similar ______
biological types
what does each term stand for in the following equation? P=G+E
P- phenotype
G- genotype
E- environment
Give an example of observable trait and measurable trait
observable: calving ease, frame size, horned condition
measurable: birth weight, weaning weight, milk yield
list two ways GXE interaction can occur
change in rank, change in magnitude
A _____ is an observed category or measure of performance for a trait of an individual
phenotype
list the two types of information a correlation value gives you about two variables or traits
relationship strength and direction (positive or negative)
correlation values range from ___ to ___
-1 to 1
list the 3 types of correlations
phenotypic, genetic, environmental
what is x and y in a regression coefficent
x- independent variable
y- dependent variable
give the formula for sample variance
σ²=Σ (Xi- mu)²/n-1
give the number of possible gametes for this genotype:
AABBCCDDEE
1 gamete
give the number of possible gametes for this genotype:
AaBbCcDdEe
32 gametes
give the number of possible gametes for this genotype:
AABbCCDdee
4 gametes
give the number of possible gametes for this genotype:
aaBBCcddEE
2 gametes
give the number of possible gametes for this genotype:
AAbbCCDdEe
4 gametes
give the formula for correlation xy
=cov(X,Y)/stdev x * stdev y
give the formula for regression y.x
cov(X,Y)/variance x
give the formula for prediction
mu y +bY.X (Xi-muX)
give the formula for regression x.y
cov(X,Y)/variance y
HWE is only proven in a large ____ mating population in the absence of ____, _____, and _____.
random; selection; migration; mutation
give the HWE equation used for genotypic frequencies
p² +2pq+q² = 1
standard deviation formula
square root of variance
covariance fomula
sum (Xi-muX)(Yi-muY)/n-1
what is the “best” animal
the one with the most output and least input, optimization>maximization, person looking at the animal determines if it is the “best”
true or false: breeds have different characteristics you select for
true
observed category or measure of performance for a trait, describes the trait
phenotype
genetic makeup of an individual
genotype
similar genotypes for traits of interest, ERT=economical relevant trait
biological type
genotype, physical enconvironment, fixed resources and mangagement
system
effect of one component on another, dependent
interactions
GxE
difference between 2+ genotypes from environment to environemnt, if there is a change there is an interaction
race of animals with in species, common origin, similar characteristics
breeds
what you breed for, caracass characteristics, replacement females, milk quality, wool production
breeding objectives
group of intermating individuals, herd or flock or breed
population
selection
choose which animals become parents
natural selection
survival of the fittest, independent of humans, HYPP, parasite resistance
artifical selection
human controled, replacements, culling
polygenic traits (quantitative)
bell shape curve, normal distribution, affected by many genes, many levels
simply inherited traits
few genes control it
mating and mating systems
gene combinations
complementary mating
best of both worlds
hybrid vigor
produce better than parents, line breeding
related mating
line breeding
can you measure a population statistics
no you have to infer from sample statistics
locus
location on a gene
do polygenic traits have multiple loci
yes which means they have lots of variance
mean
arthmitic avererage, central tendency
variation
how individuals vary for a specific trait in a population
standard deviation
measure of variations that is thought as average deviance from mean, dispersal of data
on a bell curve how much of the population is included in one standard deviation away
68%
on a bell curve how much of the population is included in two standard deviations away
95%
on a bell curve how much of the population is included in three standard deviations away
99%
can variance be negative?
no because it is squared
covariation
how two traits vary together
can covariance be negative
yes
what is one of the aspects of covariation
direction: positive mean positive deviation with positive deviation; negative mean negative deviation with positive deviation; zero means no pattern
correlation
strength of the relationship between two variables, phenotypic correlation, genetic correlation, environmental correlation
accuracy values
association between actual and predicted
regression
amount of change in variable that can be expected for a given amount of change in another variable, cause and effect, y-dependent, x-independent
what does the . in regression mean
stands for variable ON variable
what does covariance indicate
indicates a positive or negative regression and correlation
complete dominance
heterozygote same as homozygous dominant
partial dominance
heterozygous is in between the homozygous genotypes, closer to dominant
overdominance
heterozygous is outside range of homozygous genotypes
no dominance
heterozygous is it’s own phenotype, in the middle
sex linked inheritance
located on sex chromosome
sex limited inheirtance
phenotypic expression is limited
sex influenced inheirtance
expression depends on males and females
gene or allelic frequency
frequency of gene in a population
genotypic frequency
frequency of a particular one locus genotype in a population
effects of selection
increase frequency of favorable genes; genotypes catch up; select until one gene in population
outbreeding
increase heterozygousity and decrease homozygousity
threshold traits
polygenic traits that exhibit categorical phenotypes, dystocia, fertility, medelian laws and mating rules
are all traits subject to medelian laws and mating systems
yes
simple breeding approach
easy to identify genotypes, effects of specific genes, identify carriers through a test cross
polygenic breeding
more genes affecting a trait, less information about those genes, difficult to identify animals genotype, evaluate net effect- breeding value
test matings
reveal genotype for an individual for a small number of loci
factors influencing effecitiveness of selection
initial gene frequency, fitness of gene in population, degree of dominance
why do we still see so many recessive genes for true genetic defects despite strong natural and artifical selection against them?
carriers that wont beseem until mated with the right individual, sometimes mutations
what is the only part of G that can be transmitted to offspring
breeding value
projeny difference formula
=1/2 BV
additive properties
individuals gene effects are independent of each other so can add them together; BV
BV offspring formula
= ½ BV sire + ½ BV dam
GCV
the sum of the advantages of being heterozygous
why is BV important
we control it and will be passed on to offspring
repeated traits
traits with more than one performance record
producing ability
performance potential of an individual for a repeated trait
permanent environment
affects an individual performance for a repeated trait; horse train, calf hood nutrition
temporary environment
influence one performance record of individual; condition of track, mastitis
what is the only thing that changes from one performance record to another
the temporary environment
MPPA
most probable producing ability; BV, GCV, Ep, but not Et
what is the genetic model for repeated traits
P= mu +BV +GCV +Ep +Et
Note 
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