What are both Sickle-cell anemia and Huntington's chorea?

In a normal couple,half of the sons are hemophilic and half of the daughters are carriers. Where is the gene located?

The gene for haemophilia is located on the $X$ chromosome. Hence,it is normally impossible for a:

If a colour-blind man marries a woman who is homozygous for normal colour vision,the probability of their son being colour-blind is

Which of the following is a sex-linked disease?

Phenylketonuria $(PKU)$ is an inborn error of metabolism caused by the expression of recessive genes $(pp)$. In this condition,the amino acid phenylalanine is not converted into which amino acid,and what type of genetic disorder is it?