Haemophilia is more common in males because it is a ______.

(a)

Recessive character carried by Y-chromosome

(b)

Dominant character carried by Y-chromosome

(c)

Dominant trait carried by X-chromosome

(d)

Recessive trait carried by X-chromosome

ABO blood group in man is controlled by _____.

(a)

Multiple alleles

(b)

Lethal genes

(c)

Sex linked genes

(d)

Y-linked genes

Three children of a family have blood groups A, AB and B. What could be the genotypes of their parents?

(a)

I^A I^B and I^oI^o

(b)

I^A I^o and I^BI^o

(c)

I^B I^B and I^A I^A

(d)

I^A I^A and I^oI^o

Which of the following is not correct?

(a)

Three or more alleles of a trait in the population are called multiple alleles

(b)

A normal gene undergoes mutations to form many alleles

(c)

Multiple alleles map at different loci of a chromosome

(d)

A diploid organism has only two alleles out of many in the population

Which of the following phenotypes in the progeny are possible from the parental combination AxB?

(a)

A and B only

(b)

A,B and AB only

(c)

AB only

(d)

A, B, AB and O