Read the following and answer any four questions from (i) to (v).

In human, the allele for brown eyes (B) is dominant over that for blue eyes (b). A brown eyed woman marries a blue-eyed man, and they have six children. Four of the children are brown eyed and two of them are blue eyed.

(i) What is the genotype of blue-eyed offspring?

1. BB
2. Bb
3. bb
4. Cannot be determined.

 

(ii) What is the woman's genotype?

1. BB
2. Bb
3. bb
4. Cannot be determined.

 

(iii) The ovum, produced by the mother carries the gene regarding eye colour is:

1. BB
2. Bb
3. B or b
4. B only.

(iii) The ratio of brown eyed children to blue eyed children in this family is 2 : I, which deviates from typical phenotypic ratios for monohybrid inheritance. What might be the reason?

1. Gametes carrying the brown eyed allele are more viable than those with the blue-eyed allele.
2. A different pattern of inheritance other than monohybrid inheritance is involved.
3. Not all of their babies survived childbirth, thus causing a distortion in the actual ratio.
4. The actual ratio differs from the expected ratio because the sample size is too small.

 

(iv) What is the gene carried by of the man's spenn regarding the eye colour?

1. BB
2. Bb
3. b only

d. b or B.