A normal woman whose father was colour blind, is married to a normal man. The sons would be

If a boy's father has haemophilia and his mother has one gene for haemophilia; what is the chance that the boy will inherit the disease

Sickle­cell anaemia is

Haemophilia, a $X$-linked recessive disease is caused due to deficiency of

If both parents are carriers for thalassaemia, which is an autosomal recessive disorder, what are the chances of pregnancy resulting in an affected child?

Colour blindness in man is