A woman with two genes (one on each X-chromosome) for haemophilia and one gene for colour blindness on the X-chromosome marries a normal man. How will the progeny be?
 

1.	All sons and daughters are haemophilic and colour blind
2.	Haemophilic and colour blind daughters
3.	50% haemophilic colour blind sons and 50% haemophilic sons
4.	50% haemophilic daughters and 50% colour blind daughters

A hereditary disease which is never passed on from father to son is:

1. X-chromosomal linked disease

2. Autosomal linked disease

3. Y-chromosomal linked disease

4. None of the above

A polygenic inheritance in human beings is:

1. skin colour

2. sickle cell anaemia

3. colour blindness

4. phenylketonuria

In Antirrhinum (Snapdragon), a red flower was crossed with a white flower and in F₁ generation, pink flowers were obtained. When pink flowers were selfed, the F₂ generation showed white, red, and pink flowers. Choose the incorrect statement from the following:

Select the incorrect statement:

What map unit (Centimorgan) is adopted in the construction of genetic maps?