Which of the following statements is not true for cancer cells in relation to mutations?

1.	Mutations destroy telomerase inhibitor
2.	Mutations inactivate the cell control
3.	Mutations inhibit the production of telomerase
4.	Mutations in proto–oncogenes accelerate the cell cycle

A colour-blind man marries a woman with normal sight who has no history of colour blindness in her family. What is the probability of their grandson being colour blind? (consider the grandsons only through son)

1. 0.5

2. 1

3. Nil

4. 0.25

In his classic experiments on pea plants Mendel did not use?

1. Seed color

2. Pod length

3. Seed shape

4. Flower position

A pleiotropic gene:

The movement of a gene from one linkage group to another is called:

Fruit colour in squash is an example of:

1. Recessive epistasis

2. Dominant epistasis

3. Complementary genes

4. Inhibitory genes

A man whose father was colour blind marries a woman who had a colour blind mother and a normal father. What percentage of male children of this couple will be colour blind?

1. 25%

2. 0%

3. 50%

4. 75%

Sickle cell anaemia is: