Probability of Heredity Punnett Squares Probability of Heredity

Punnett Square A tool used to calculate the probability that offspring will have certain traits

Alleles The different forms of a trait You inherit two alleles for each gene Ex: the alleles for eye color are blue, brown, hazel, green, etc.

Homozygous The two alleles for a gene are alike Either two dominant (TT) or two recessive (tt) Also called purebred

Heterozygous The two alleles for a gene are different Genotype has one dominant and one recessive (Rr) Also called hybrid

Cross The genetic information from two different parents are combined Can be controlled to produce desired traits

Incomplete Dominance Neither allele is stronger than the other The alleles blend together to create a ‘in-between’ variety Ex: red flowers crossed with white flowers produce pink flowers

Codominance Neither allele is stronger than the other Both alleles appear Ex: red flowers crossed with white flowers produce red and white spotted flowers

P Generation The parents in a genetic cross

F1 Generation The offspring produced by a genetic cross