According to Mendel’s law of dominance, when a pure‑bred tall pea plant (TT) is crossed with a pure‑bred dwarf plant (tt), the F1 generation shows which phenotype?

Step-by-step solution

1. Identify the genotypes of the parents: TT (tall) and tt (dwarf).
2. According to the law of dominance, the allele T (tall) is dominant over t (dwarf).
3. All gametes from the tall parent carry T, and all gametes from the dwarf parent carry t.
4. Fertilisation gives genotype Tt for every offspring.
5. Since T is dominant, every Tt individual shows the tall phenotype.
6. Therefore, all F1 plants are tall.

Concept tested: Law of dominance

Published 21 August 2026 · How this solution was prepared and checked

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