Question

A family consists of two parents and their five children and the pedigree chart below shows the inheritance of the trait colour blindness . 

(i) Who is colour blind in parents - Father or Mother?
(ii) How many daughters and sons have beeen born in the family?
(iii) What does the child 1 indicate about this trait?
(iv) Complete the depiction of all probabilities of the trait among the children 2-5 in the chart.
(v) On which chromosome is the gene of this trait located?
(vi) Name one other trait in humans which follows the similar mode of inheritance.

Answer 1

(i) Father is color blind.
(ii) 3 daughters and two sons.
(iii) Child 1 is color blind.
(iv) All daughters from 2-5 are carriers while all the sons are normal.
(v) X chromosome.
(vi) Haemophilia.