Same chapter3 marksDifficulty: Medium
Name three genetic disorders in human beings and state the cause of each.
Principles of Inheritance and Variation
3 marksDifficulty: Medium
Describe the ABO blood group system as an example of multiple allelism and codominance.
Original Khojo Papers practice question — not from a past board paper.
Answer
The gene for the ABO system has three alleles, IA, IB and i, so it is an example of multiple allelism, though any one person carries only two. IA and IB are codominant, so a person carrying both has group AB with both antigens; i is recessive to both, so only ii gives group O.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Six genotypes give four phenotypes.
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