Question on: JAMB Biology - 2001

Here's the explanation:

• Understanding the Problem: The question describes a classic Mendelian genetics problem. The key is that the offspring ratio is 1:1 (half tall, half dwarf). This indicates that one parent must be heterozygous and the other homozygous recessive.
• Analyzing the Options:
  • A. TT, TT: If both parents were homozygous dominant (TT), all offspring would be tall (TT). This doesn't match the 1:1 ratio.
  • B. Tt, tt: This is the correct answer.
    • Tt (tall) crossed with tt (dwarf)
    • Possible gametes: T, t from Tt and t from tt
    • Offspring genotypes: Tt, tt

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