Monohybrid Crosses

Monohybrid Cross

A genetic cross tracking the inheritance of one single trait.

Punnett Square

A grid tool used to predict genetic outcomes of a cross.

Genotypic Ratio

The mathematical ratio of genotypes expected in offspring (e.g., 1 $BB$ : 2 $Bb$ : 1 $bb$).

Phenotypic Ratio

The mathematical ratio of physical traits expected in offspring (e.g., 3 dominant : 1 recessive).

Autosomal Complete Dominance

Standard trait on non-sex chromosomes where dominant hides recessive (Example: Pea color).

Autosomal Incomplete Dominance

Non-sex chromosome trait where alleles blend (Example: Pink Snapdragon flowers).

Autosomal Co-Dominance

Non-sex chromosome trait where both show up fully (Example: ABO Blood Type AB).

Sex-linked Alleles

Traits carried on sex chromosomes, usually the X (Example: Red-green colorblindness).

Test Cross

Crossing a dominant phenotype individual with a homozygous recessive to find its genotype.