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Biology · Ch 3 — Inheritance and Variation

Mendel's Laws of Inheritance

3.3

Mendel's Laws of Inheritance

Working purely from the numerical patterns in his pea-plant crosses, Mendel arrived at three fundamental postulates about how heredity works. These were later formalised into three laws — the Law of Dominance, the Law of Segregation and the Law of Independent Assortment — which together explain both the uniform appearance of the F1 generation and the predictable ratios recovered in F2. Each law is examined in its own sub-section below, since each rests on a distinct piece of evidence: dominance on the monohybrid F1, segregation on the reappearance o …