4. Mendel's F₂ data (6,022 yellow: 2,001 green) is often cited as a cornerstone of classical genetics.
a) Calculate the phenotypic ratio and explain how this specific mathematical outcome supports the Law of Segregation.
b) If the yellow F₁ plants had been 'test-crossed' with the original true-breeding green parents instead of self-pollinated, what phenotypic ratio would you expect in the resulting offspring? Justify your answer