In man,albinism is due to the non-synthesis of melanin in the absence of:

Colour blindness in man is

$A$ color-blind woman marries a man with normal vision. In their offspring,.........

Haemophilia is:

$A$ man with normal vision whose father was colourblind marries a woman whose father was also colourblind. Suppose their first child is a daughter,what are the chances of this child being colourblind (in $\%$)?

$A$ sex-linked recessive gene $c$ produces red-green colour blindness in humans. $A$ normal woman whose father was colourblind marries a colourblind man. Of all the girls born to these parents, what percentage is expected to be colourblind?