Practice: Simple Mendelian Inheritance

Vocabulary and key concepts from the Simple Mendelian Inheritance practice problems, including testcrosses, probability calculations, and autosomal recessive traits.

Normal color (Corn Snake)

The dominant phenotype in corn snakes when crossed with albino varieties.

Albino (Corn Snake)

A recessive trait in corn snakes that produces a $3:1$ ratio of normal to albino offspring in the second-generation (F2) progeny ($32$ normal to $10$ albino).

Testcross

A procedure used to determine if an individual with a dominant phenotype is heterozygous or homozygous by crossing them with an individual expressing the recessive trait (e.g., abnormal legs).

Aa bb CC Dd ee Ff (Gamete Count)

A genotype that can produce $8$ different types of gametes.

Aa Bb CC Dd ee Ff (Gamete Count)

A genotype that can produce $16$ different types of gametes.

Multiplication Rule (Genetics)

The method used to find the probability of a specific gamete combination, such as the probability of $D$ and $F$ occurring together ($25\%$ if each has a $50\%$ chance).

Hybrid

A genetic term for being heterozygous at a specific locus, such as the "B" gene in a cross resulting in $100\%$ $Bb$ offspring.

Pure-breeding

A term for being homozygous at a locus, such as the genotype $MM$, which occurred in $50\%$ of the offspring in the provided cross.

Cystic fibrosis

An autosomal recessive disease where two healthy parents ($Ff$ and $Ff$) have a $25\%$ chance of producing an affected child ($ff$).

Autosomal recessive

A type of inheritance where a disease can skip generations and appear in the offspring of two healthy (carrier) parents.

Genetic carrier

An individual who MUST carry a recessive allele, identified in pedigrees as parents of affected individuals ($6$, $7$, $13$, $14$) or children of affected individuals ($21$, $22$, $23$, $24$, $25$).

Heterozygous Gamete Probability

In an individual with genotype $Aa$, the percentage of gametes that will carry the $a$ allele is $50\%$.

Homozygous Gamete Probability

In an individual with genotype $bb$, the percentage of gametes that will carry the $b$ allele is $100\%$.