Biology Inheritance / Variation & Genetics ETEA 2022
PMDC Verified Question 58 of 94
A man of blood group A marries a woman of blood group B and they have one child. Which one of the following statements about the child's blood is correct?
A
It could be group A only
B
It could be group AB only
C
It could be group A or group B only
D
It could be any of the groups A, B, AB and O
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option D: It could be any of the groups A, B, AB and O
Concept:

The ABO blood groups A and B can be either homozygous or heterozygous, which significantly affects the possible phenotypes of offspring.

Solution:

If the man (Group A) is heterozygous (\(I^A i\)) and the woman (Group B) is heterozygous (\(I^B i\)), the Punnett square is:

♀ \ ♂IAi
IBIAIB (AB)IBi (B)
iIAi (A)ii (O)

  • As shown, the cross can produce offspring of all four possible phenotypes: A, B, AB, and O.
  • Therefore, the child could have any of these blood groups.


Why other options are incorrect:

  • Options A, B, and C fail to account for the possibility that both parents carry the recessive \(i\) allele.

Quality & Fidelity Assurance: Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.

Previous Question All Inheritance / Variation & Genetics MCQs Next Question

Want to solve full-length papers under timed exam conditions?

Practice with zero-scroll lockdown sprints, dynamic latency zone timers, live peer selection telemetry, and the automated Amber mistake recovery loop.

Enter Arena Sprint iOS App Android App