Medium
In pea plants, tallness (T) is dominant over dwarfness (t). Two heterozygous tall plants (Tt × Tt) are crossed. What is the probability that an offspring is dwarf?
Explanation
Explanation
Step 1: Parent gametes: each Tt plant forms T and t gametes in equal numbers.
Step 2: Draw the Punnett square: T×T = TT, T×t = Tt, t×T = Tt, t×t = tt.
Step 3: Genotype ratio TT : Tt : tt = 1 : 2 : 1, and phenotype ratio tall : dwarf = 3 : 1.
Step 4: A plant is dwarf only when it is tt, which is 1 out of 4 = 25%.
Answer: 25%.
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