WAEC Biology 1993 Question 47

Question 47

Mendelian Inheritance

The table below indicates the result of an experiment during which grains of different colours in two maize cobs were counted
Maize Cob I: White 30, Pink 60, Red 30
Maize Cob II: White 50, Pink 99, Red 49
Which of the following ratios agrees with the result?

  1. A.9:3:3
  2. B.1:2:1
  3. C.1:3:1
  4. D.2:1:1
  5. E.2:3:2
Show the answer and explanation

Answer: B (1:2:1)

Explanation

Cob I: 30 : 60 : 30 = 1 : 2 : 1; cob II: 50 : 99 : 49 ≈ 1 : 2 : 1 (incomplete dominance).