Two heterozygous tall pea plants (Tt × Tt) are crossed. What is the probability that an offspring is short (tt)?
Answer and explanation
Correct answer: A. 25%
- Step 1: The cross gives TT : Tt : Tt : tt, so one in four offspring is tt.
Answer
25%.
Why not the others: 50%: 50% is the chance of being heterozygous. 75%: 75% is the chance of showing the dominant (tall) phenotype. 100%: not all offspring can be short from two tall parents carrying T.
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