Question

Corn plants may be tall (TT or Tt) or short (tt). The breeding of two parent corn plants results in offspring that are all tall. What is the probability that both of the parents in this example are homozygous recessive?

Answer 1

Answer:

0%

Explanation:

• The probability that both of the parents are homozygous recessive is zero.
• In our case, The gene for tallness is dominant over the gene for dwarfism
• Therefore; TT is homozygous dominant while tt is homozygous recessive and Tt is heterozygous.
• Heterozygous genotype (Tt) will exhibit a tall phenotype.
• When two parents are crossed and all the offsprings are tall then the possible genotype of the parents is either;

1. Homozygous dominant for both parents or  

       TT x TT

    2. One parent is homozygous dominant and the other is homozygous recessive.

        TT x Tt

• Therefore, the probability of having both parents as homozygous recessive when all the offspring are tall is Zero.