The incorrect statement with regard to haemophilia is

• It is a sex - linked disease

• It is a recessive disease

• It is dominant disease

• It is dominant disease

If both parents are carriers for thalassemia, which is an autosomal recessive disorder, what are the chances of pregnancy resulting in an affected child?

• No Chance

• 50%

• 25%

• 25%

Which enzyme/s will be produced in cell in which there is a non-sense mutation in the lac Y gene?

• beta - galactosidase

• Lactose permease

• Transacetylase

A gene showing codominance has:

• One allele dominant on the other

• alleles tightly linked on the same chromosome

• alleles that are recessive to each other

• alleles that are recessive to each other

15.

The term "linkage" was coined by

• T.H. Morgan

• T. Bover

• G. Mendel

• G. Mendel

In the following human pedigree, the filled symbols represent the affected individuals. Identify the type of given pedigree. 

• Autosomal dominant

• X-linked recessive

• Autosomal recessive

• Autosomal recessive

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?

• 0.5

• 1

• Nil

• Nil

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

• Seed colour

• Pod length

• Seed shape

• Seed shape

Fruit colour in squash is an example  of 

• recessive epistasis

• dominant epistasis

• complementary genes

• complementary genes

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?

• 100%

• 0%

• 25%

• 25%