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Tuesday, 18 August 2026
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Biology Past Questions and Answers

Topic: Heredity

Jamb Biology Questions - Heredity

Question 46:
A man and his wife are both heterozyous for the sickle-cell trait. The likely percentage of their offspring that will be either carriers or sicklers is
  • A 75%
  • B 50%
  • C 25%
  • D 100%
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Question 47:
If the pair of alleles for baldness is given as Bb, a female carrier will be denoted by
  • A X<sup style='font-size: smaller;'>b</sup>Y<sup style='font-size: smaller;'>B</sup>
  • B X<sup style='font-size: smaller;'>B</sup>X<sup style='font-size: smaller;'>B</sup>
  • C X<sup style='font-size: smaller;'>B</sup>Y
  • D X<sup style='font-size: smaller;'>Bb</sup>X<sup style='font-size: smaller;'>b</sup>
View Answer & Explanation
Question 48:
An organism that has been extensively used to test the chromosomes theory of heredity is
  • A Drosophila melanogaster
  • B Muscar domestica
  • C Zea mays
  • D Homo sapiens
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Question 49:
A feature associated with the Y-chromosome in human is
  • A Long eyelashes
  • B Prominent fingernails
  • C Facial hairs
  • D Enlarged breast
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Question 50:
Identical twins inherit their genes from
  • A Different eggs and sperms
  • B The same egg and sperm
  • C Two eggs and a sperm
  • D One egg and two sperms
View Answer & Explanation