In a cross between a normal male and a female carrier for haemophiliac disease, the percentage of their sons expected to suffer the disease as haemophiliac is ____________
A. \(25 \%\) B. \(50 \%\) C. \(70 \%\) D. \(45 \%\)
Correct Answer: B
Explanation
\(25 \%\) of the offsprings will be haemophiliac \((50 \%\) of the mai offsprings), \(25 \%\) of the offsprings will be carrier (50\% of the female offspring), \(50 \%\) of the offspring will be normal ( \(50 \%\) of the male and \(50 \%\) of the female). \(XhX\) carricr female \((25 \%\) of total offsprings or \(50 \%\) (1/2) of the female off springs); \(X ^{ h } Y\) - haemophiliac male \((25 \%\) of the offsprings or \(50 \%\) (1/2) of the male offsprings); \(XX\) - normal female \((25 \%\) of the offpsrings or \(50 \%\) of the female offsprings); \(XY\) - normal malc ( \(25 \%\) of the offsprings or \(50 \%(1 / 2)\) of the male offsprings).