Question

A dwarf pea plant was treated with gibberellic acid and it becomes as tall as a tall pea plant. If these treated pea plants are crossed with pure tall pea plants, the phenotypic ratio in $F_1$ generation will be:

• A. All tall
• B. 50% tall, 50% dwarf
• C. 75% tall, 25% dwarf
• D. 25% tall, 75% dwarf

Hint:

Gibberellic acid induces tall phenotype without altering the genotype.

Answer 1

The Correct Option is A

The dwarf plant treated with gibberellic acid does not undergo a genetic change—it remains genetically dwarf. If it is crossed with a pure tall plant (TT), the offspring would all be heterozygous (Tt), and phenotypically tall. Hence, all tall offspring are produced in F₁ generation.