CBSE 2025 · Region 2 · Set 1 · Q18 · 2 marks
Study the given pedigree chart in which neither of the parents shows the trait but the trait is present in both male and female children.Answer the following questions :(a)Write about the trait, also explain the inheritance of such trait in the progeny on the basis of given pedigree chart.(b)Give one example of such trait in human beings.
Study the given pedigree chart in which neither of the parents shows the trait but the trait is present in both male and female children.
Answer the following questions :
(a)
Write about the trait, also explain the inheritance of such trait in the progeny on the basis of given pedigree chart.
(b)
Give one example of such trait in human beings.
Marking-scheme solution
(a)
Autosomal recessive trait
Normal carrier parents / Heterozygous individuals , transfer defective gene to both male and female progeny producing affected individuals or homozygous recessive individuals //
(b)
Sickle cell anaemia / Cystic fibrosis / Phenylketonuria / Thalassemia /
Principles of Inheritance and VariationMendel’s Laws of InheritanceAnalysevery_short_answermedium
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CBSE Class 12 Biology past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.