Complete question:
If a heterozygous plant is allowed to self-pollinate, what proportion of the offspring will also be heterozygous?
1/4
1/3
1/2
2/3
all of them
Answer:
1/2
Explanation:
Let's assume that the genotype of the plant is Tt. The two plants with "Tt" genotype are crossed. Each of the parent plants would produce two types of gametes in equal proportion. They will for 1/2 gametes with the allele "T" and rest 1/2 gametes with the allele "t".
The genotype ratio of the progeny would as following:
Tt x Tt = 1/4 TT: 1/2 Tt: 1/2 tt
Therefore, 1/2 progeny is heterozygous (1/2 Tt)
