Double lines in pedigree analysis show

The distortion of hemoglobin under low oxygen tension is a characteristic of which of the following?

Carrier of genes of colour blindness are present in

In the formation of the $\beta$-globin chain of hemoglobin,when valine replaces glutamic acid,the shape of the red blood cell becomes sickle-shaped,which leads to ....

If both the mother and father are without pigments (albinism),then:

$A$ normal-visioned man whose father was colour-blind,marries a woman whose father was also colour-blind. They have their first child as a daughter. What are the chances that this child would be colour-blind?