Q1. [2] § 8.2.2 Rules for the Inheritance of Traits – Mendel's Contributions
Mendel crossed two pea plants with two visible contrasting characteristics and found that there were no half-way characteristics in the plants of F1 progeny. Explain the reason for this observation of Mendel.
Previously asked in CBSE board exam
2022 31/3/1 Q6(a)
Generated by claude-sonnet-4-6 · 2026-06-15 06:53 · grounding rag
Model Answer
In Mendel's cross, each trait is controlled by two factors (genes). One factor came from each parent. Since only one parental trait (tall) appeared in F1, the trait from one parent was dominant over the other (recessive). The dominant trait completely masked the recessive one, so no intermediate or halfway characteristics were observed.
Source: Chapter 8, Section 8.2.2
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Explanation
- The examiner expects you to use the terms dominant and recessive correctly.
- The key idea is that one allele completely masks the other — there is no blending — which is why F1 shows only the dominant trait, not a mix.
- Avoid vague phrases like "stronger gene"; say "dominant trait masks the recessive trait."
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