A pure breeding tall pea plant was crossed to a dwarf plant what will be the frequency of dwarf plants in F2?
Correct answer: A. 0.25
- A. 0.25
- B. 0.5
- C. 0
- D. 1
Explanation
Assuming that the tall plant is homozygous dominant (TT) for height and the dwarf plant is homozygous recessive (tt), the F1 generation will all be hybrid Tt plants (heterozygous for height). When the F1 plants are crossed among themselves, the Punnett square predicts that the offspring will have a genotype ratio of 1 TT: 2 Tt: 1 tt. Therefore, the frequency of dwarf plants in the F2 generation would be 25% (or 1/4). Hence only option A is correct.
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