Term
|
Definition
passing of traits or characteristis from parent to offspring through inheritance of genes |
|
|
Term
Gregor Mendel introduced the idea of : |
|
Definition
|
|
Term
|
Definition
A specific genetic unti ontrolling a single genetic trait is passed on from generation to generation. |
|
|
Term
true-breeding individuals |
|
Definition
- if crossed with self, would exhibit exact same traits and genotypes |
|
|
Term
|
Definition
when 2 different alleles present in a genotype, only the trait encoded by one of the alleles is observed in phenotype |
|
|
Term
calculating Chi-squared:
expected |
|
Definition
multiply the probability of that phenotype by the total # of progeny counted |
|
|
Term
|
Definition
heterozygotes show a distinct intermediate phenotype, not seen in homozygotes |
|
|
Term
I.D.:
phenotypic ratios are same or different?
3:1 or 1:2:1? |
|
Definition
|
|
Term
C.D.: phenotypic and genotypic ratios are same or different?
3:1 or 1:2:1? |
|
Definition
different:
phenotypic ratio : 3:1
genotypic ratio: 1:2:1 |
|
|
Term
|
Definition
two alleles affect the phenotype in seperate, distinguishable ways :
-- production of new phenotypes in offspring with parental phenotypes, & the heterozygote phenotype where both of the parental traits appear together
ex - blood types AB |
|
|
Term
|
Definition
a mutant allele that may cause death
(homozygous recessive individuals die, 3:1 ratio changes) |
|
|
Term
essential genes: when mutated -> |
|
Definition
|
|
Term
|
Definition
an organism that has normal (wild-type) genotype but a mutant phenotype
-mutant appearance caused by an environmental factor
(drugs or pollution can cause birth defects, etc) |
|
|
Term
Four types of lethal alleles: |
|
Definition
early onset
late onset
conditional
semi-lethal (kills some mutant ind's in pop.) |
|
|
Term
|
Definition
can code for either dominant or recessive traits, but do not actually cause death unless an organism carries 2 copies of the allele |
|
|
Term
Gene interactions that produce novel phenotypes: |
|
Definition
when 2 allelic pairs (genes at 2 loci) in a dihybrid crossafect the same phenotypic trait |
|
|
Term
|
Definition
the interaction between 2+ genes to control a single phenotype, masking of the expression of one gene by another gene at a different locus |
|
|
Term
|
Definition
gene that masks other gene |
|
|
Term
|
Definition
gene whose effect is masked |
|
|
Term
Difference between epistasis and dominance: |
|
Definition
dominance: phenotype is determined by different alleles of the same gene locus
epistasis: phenotype is determined by different alleles of two or more different gene loci |
|
|
Term
|
Definition
2 copies of epistatis allele must be present to mask expression of hypostatic gene |
|
|
Term
|
Definition
single copy of epistatic allele sufficient to mask expression of hypostatic gene |
|
|
Term
|
Definition
|
|
Term
bichemical explanation of complimentary gene action |
|
Definition
epistatic interaction often arise because 2+ different proteins encoded at different gene loci participate in common cellular function |
|
|
Term
|
Definition
determine whether mutations that affect a characteristic are at the same locus (allelic) or at different gene loci |
|
|
Term
|
Definition
1 gene affects multiple phenotypic characters
|
|
|
Term
|
Definition
the proportion of individuals with a given genotype who exhibti the expected phenotype for that genotype |
|
|
Term
|
Definition
genotype does not give expected phenotype |
|
|
Term
|
Definition
degree to which character is expressed |
|
|