CBSE 2025 · Region 4 · Set 3 · Q23 · 3 marks
Gregor Mendel used true-breeding pea lines to conduct his hybridisation experiments in garden pea.(a)Explain what is meant by true-breeding pea lines.(b)State the three important points of law of dominance as proposed by Gregor Mendel.
Gregor Mendel used true-breeding pea lines to conduct his hybridisation experiments in garden pea.
(a)
Explain what is meant by true-breeding pea lines.
(b)
State the three important points of law of dominance as proposed by Gregor Mendel.
Marking-scheme solution
(a)
True-breeding line is one that having undergone continuous self-pollination, shows the stable trait inheritance, and expression for several generations.
(b)
Law of dominance
–
Characters are controlled by discrete unit called factors
–
Factors occur in pairs.
–
In a dissimilar pair of factors one member of the pair dominates (dominant) the other (recessive).
Principles of Inheritance and VariationMendel’s Laws of InheritanceUnderstandshort_answereasy
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CBSE Class 12 Biology past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.