1. Probability of Heredity
Punnett Squares
Probability of Heredity

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

3. 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.

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

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

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

7. 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

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

9. P Generation
The parents in a genetic cross

10. F1 Generation
The offspring produced by a genetic cross