6.5

Punnett Square

• Grid system to predict all possible genotypes from a cross.
• Genotype ratio: count squares with each genetic combination.
• Phenotype ratio: ratio of phenotypes in the same generation.
• Parents have two alleles for each gene.
• Chromosomes separate during meiosis.

Types of Crosses

• Monohybrid cross: inheritance of one trait.
• Dihybrid cross: inheritance of two traits.

Law of Independent Assortment

• Allele pairs separate independently during meiosis.
• Different traits inherited separately.

Probability

• Likelihood of a particular event.