Punnett Square Worksheet. For each cross, draw a Punnett square, then list the percentages of genotypes and phenotypes. Be sure to remember that the capital letter represents dominance. 1. Green beans are dominant over yellow beans. A hybrid green bean plant (Gy) is crossed with a green bean plant (Gy). 2. A hybrid green bean plant (Gy) is crossed with a purebred yellow bean plant (yy). 3. Tall bean plants are dominant over short bean plants. A purebred tall plant (TT) is crossed with a hybrid tall plant (Ts). 4. A homozygous tall plant (TT) is crossed with a short plant (ss). 5. Two hybrid red flowers (Rw) are crossed (red flowers are dominant, white flowers are recessive) 6. A heterozygous red flower is crossed with a white flower. 7. A homozygous dominant white chicken is crossed with a heterozygous white chicken, the recessive phenotype is brown. 8. A purebred dominant brown mouse is crossed with a heterozygous brown mouse (tan is the recessive phenotype). 9. Two heterozygous white rabbits are crossed (white fur is dominant to black). 10. A hybrid white rabbit is crossed with a black rabbit. 11. A homozygous tall bean plant is crossed with a heterozygous plant.