Question

select the correct answer.
when two plants, both tall, were crossed, they produced some offspring that were dwarves. assuming that the height of the plant is controlled by a single gene and the allele for the tall plant is dominant, what is the genotype of the parents?
a. tt and tt
b. tt and tt
c. tt and tt
d. tt and tt

Explanation:

Step1: Determine the recessive trait

Since the offspring has the dwarf trait (recessive), and the height is controlled by a single gene. Let \(T\) represent the dominant allele (tall) and \(t\) represent the recessive allele (dwarf).

Step2: Analyze the parents' genotypes

For two tall - parent plants to produce a dwarf offspring (\(tt\)), each parent must contribute a recessive allele (\(t\)). So both parents must have the genotype \(Tt\) (heterozygous). Because if a parent was \(TT\), it could only pass on the \(T\) allele, and there would be no way to get an \(tt\) offspring.

Answer:

B. \(Tt\) and \(Tt\)