Knowing that albinism is determined by a recessive gene in man; presence of albinism in children born to a couple proves that
Both the father and the mother are heterozygous for albinism
The father is homozygous normal but the mother is heterozygous or vice versa
The father is homozygous for albinism but the mother is heterozygous or vice versa
$(a)$ and $(c)$ are correct
The scientists who have given the theory of linkage are
Haemophilia is also called
In a cross between white-flowered parents, $F_1$ progeny was uniformly purple-flowered. The $F_2$ progeny showed a phenotypic ratio $9 : 7$ between purple-flowered and white-flowered plants. The above result indicates that the flower colour is controlled by
If interference is complete or cent percent then the frequency of observed double crossover will be
Which of the following phenomena leads to variation in $DNA$?