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