Question

in pea plants, the allele for a tall plant is dominant over the allele for a short plant. you have a true - breeding recessive plant. which statement is true?
a. the plants phenotype is short, and its genotype is tt.
b. the plants genotype is short, and its phenotype is tt.
c. the plants phenotype is short, and its genotype is tt.
d. the plants genotype is short, and its phenotype is tt.

Explanation:

• Phenotype refers to the observable physical trait (e.g., short or tall in pea plants).
• Genotype is the genetic makeup. A true - breeding recessive plant has two recessive alleles. If the allele for tall (\(T\)) is dominant over short (\(t\)), a short plant (phenotype) must have a genotype of \(tt\) (since \(TT\) would be tall and \(Tt\) would also be tall as \(T\) is dominant).
• Option A: \(TT\) genotype would result in a tall phenotype, so A is wrong.
• Option B: Genotype is the genetic code (\(tt\) or \(TT\) etc.), not the physical trait (short/tall). Phenotype is the physical trait. So B is wrong.
• Option D: Similar to B, genotype is not the physical trait. Also, \(TT\) is a tall genotype. So D is wrong.

Answer:

C. The plant's phenotype is short, and its genotype is \(tt\).