Genetics: Punnett Square

A green pea plant (Gg) is crossed with a yellow pea plant (gg). Describe the genotype of the offspring. (Be sure to remember that the capital letter is dominant).

• 50% heterozygous and 25% homozygous recessive
• 50% heterozygous and 50% homozygous recessive
• 100% homozygous recessive
• 25% heterozygous and 50% homozygous

A tall plant (TT) is crossed with a tall plant (Tt). What is the phenotype of the offspring?

• 50% homozygous dominant; 50% heterozygous; 100% tall
• 100% homozygous dominant; 100% tall
• 25% homozygous dominant; 75% heterozygous; 100% short
• 50% homozygous dominant; 50% heterozygous; 100% short

A tall plant (Tt) is crossed with a short plant (tt). What is the genotype of the offspring?

• 25% heterozygous; 75% homozygous
• 100% homozygous dominant
• 100% heterozygous
• 50% heterozygous; 50% homozygous dominant

A tall plant (Tt) is crossed with a short plant (tt). What is the phenotype of the offspring?

• 75% tall; 25% short
• 25% tall; 75% short
• 50% tall; 50% short
• 100% tall

A white flower (rr) is crossed with a white flower (rr). What is the genotype of the offspring? Draw a Punnett square and answer the question.

• 100% homozygous dominant
• 100% heterozygous dominant
• 100% homozygous recessive
• 100% heterozygous recessive

A white flower (rr) is crossed with a white flower (rr). What is the phenotype of the offspring? Draw a Punnett square and answer the question.

• 100% white
• 75% white; 25% red
• 75% red; 25% white
• 100% red

A black chicken (BB) is crossed with a black chicken (BB). What is the genotype and phenotype of the offspring? Draw a Punnet square and naswer this question.

• 100% heterozygous; 50% black
• 100% homozygous dominant; 100% black

A red flower (Rd) is crossed with a white flower (rr). What is the genotype of the offspring? Draw a Punnett square and answer this question.

• 50% heterozygous; 50% homozygous dominant
• 100% homozygous dominant
• 100% homozygous recessive
• 50% heterozygous; 50% homozygous recessive

A homozygous dominant brown mouse (BB) is crossed with a heterozygous brown mouse (tan is the recessive color). List the offspring genotype and phenotype.

• 50% homozygous dominant; 50% heterozygous and 100% tan
• 25% homozygous dominant; 75% heterozygous; 100% brown
• 50% homozygous dominant; 50% heterozygous and 100% brown
• 75% homozygous dominant; 25% heterozygous and 100% tan

Two heterozygous white (brown fur is recessive) rabbits are crossed. What is their genotype?

• 25% homozygous dominant; 25% homozygous recessive; 50% heterozygous
• 50% homozygous dominant; 50% heterozygous
• 25% homozygous domestic; 75% homozygous recessive