General Genetics Quiz 1 Review

Flashcards covering guinea pig inheritance patterns, F2 phenotypic ratios in epistasis, and the stages/mechanisms of meiosis based on the BIOL 3100 Quiz 1 transcript.

Jill's Hypothesis (Guinea Pig color)

The color inheritance is explained by incomplete dominance where white ($AA$) and orange ($aa$) parents produce all cream ($Aa$) offspring.

Jack's Hypothesis (Guinea Pig color)

The color gene has 3 different alleles with no incomplete dominance, where dominance relationships like C^o > C^c > C^w or C^o > C^w > C^c are possible.

9 WT : 7 mutant ratio

The phenotypic ratio in F2 when both genes A and B show full dominance (A > a, B > b) and both are needed for the development of the wildtype phenotype.

15 WT : 1 mutant ratio

The phenotypic ratio in F2 when both genes A and B show full dominance (A > a, B > b) and either gene is sufficient for the development of the wildtype phenotype.

$$P( ext{mutant}) = P(aa) + P(bb) - P(aa)P(bb)$$

The formula used to calculate the probability of a mutant phenotype when both genes are needed for the wildtype phenotype, resulting in a probability of $7/16$.

Recombination processes in meiosis

Eukaryotes undergo two processes: crossing over for linked genes and independent assortment for unlinked genes.

Crossing over

A process occurring in prophase of meiosis I that helps homologous chromosomes align to form a tetrad.

Tetrad

A structure formed during prophase of meiosis I consisting of two sister chromatids for each of the two homologous chromosomes.

Segregation of homologs

An event occurring in anaphase of meiosis I where alleles are distributed into daughter cells because they are located on homologs.

Anaphase of meiosis II

The specific stage of meiosis where sister chromatids segregate.

$$2^n$$

The number of different gametes produced by a heterozygote for $n$ genes due to crossing over and independent assortment.

$$2^{-n}$$

The frequency at which each gamete genotype is produced for unlinked genes in a heterozygote for $n$ genes.