This document provides 4 examples of Punnett square problems involving different traits. It asks what the genotype and phenotype ratios would be if: 1) A blond haired man mates with a homozygous dominant brown haired woman. 2) A rat with a fluffy tail mates with a heterozygous rat. 3) Superman, who is homozygous recessive for super powers, mates with Lois Lane who is heterozygous. 4) A heterozygous giraffe mates with a homozygous dominant long necked giraffe. The reader is prompted to solve each problem using Punnett squares to determine the possible genotypes and phenotypes of the offspring.

1. Punnett Square
Practice

2.  Blond hair is b and brown hair is B. If a
man with blond hair marries a woman
who is homozygous dominant, what will
the genotype and phenotype ratios be?

3.  Fluffy tails (f) are recessive to not fluffy
tails (F). If a rat with a fluffy tail mates
with a rat who is heterozygous, what will
the genotype and phenotype ratios be?

4.  Super powers (s) are recessive to not
having super powers (S). If Superman,
who is homozygous recessive, has
children with Lois Lane, who is
heterozygous for super powers, what will
the genotype and phenotype ratios be?

5.  In giraffes, long necks (N) are dominant
to short necks (n). If a giraffe who is
heterozygous for necks mates with a
giraffe who is homozygous dominant,
what will the genotype and phenotype
ratios be?