Cross two pea plants and predict their babies! T = Tall (dominant), t = short (recessive).
Trait: Plant height · T (Tall) is dominant over t (short)
🌱 Parent 1
🌱 Parent 2
Phenotype ratio
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Genotype ratio
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🧠 The Big Idea
Genes come in pairs (alleles) — one from each parent. A dominant allele (T) shows even if only one copy is present; a recessive one (t) shows only as tt.
Mendel's classic Tt × Tt cross gives the famous 3 : 1 phenotype ratio (3 Tall : 1 short).
Variations like these, over many generations, are the raw material of evolution.