CBSE 2024 · Region 2 · Set 2 · Q26 · 3 marks
"Human blood group (ABO group) inheritance is a good example of multiple allelism and co-dominance." Justify the statement.
Marking-scheme solution
Human blood group inheritance is regulated by the gene ‘I’ which is
present in more than two allelic forms – IA, IB, i/Hence human blood group inheritance is controlled by more than two alleles that is called multiple allelism.
When IA and IBare present together in blood group AB they both
express their own types of sugars, because both the dominant alleles hence show co-dominance.Principles of Inheritance and VariationInheritance of One GeneUnderstandshort_answermedium
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CBSE Class 12 Biology past-paper question from the 2024board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.