CBSE 2024 · Region 1 · Set 1 · Q26 · 3 marks
In a family, the father, the daughter and the son are colour blind, whereas the mother has normal vision. Do you think the son and the daughter have inherited the disease from their father ? Work out a cross to justify your answer.
Marking-scheme solution
No,
Son inherited disease from the mother and daughter inherited disease from both mother and father.
Mother Father
XCX X XCY
Normal (Carrier) Colour blindXCXC – Colour blind daughter; XCX – Carrier daughter; XCY – Colour blind son; XY – Normal son.
Principles of Inheritance and VariationSex DeterminationAnalyseshort_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.