Question

Match Column- I with Column - II and select the CORRECT option from the codes given below.

	Column - I		Column - II
(1)	Autosomal recessive trait	(i)	Down’s syndrome
(2)	Sex-linked recessive trait	(ii)	Phenylketonuria
(3)	Metabolic error linked to an autosomal recessive trait	(iii)	Haemophilia
(4)	Additional $21^{st}$ chromosome	(iv)	Sickle cell anaemia

• A. 1- (ii), 2 - (i), 3 - (iv), 4 - (iii)
• B. 1- (iv), 2 - (i), 3 - (ii), 4 - (iii)
• C. 1- (iv), 2 - (iii), 3 - (ii), 4 - (i)
• D. 1- (iii), 2 - (iv), 3 - (i), 4 - (ii)

Answer 1

Answer: (C)

Chromosomal disorder occurs when there is addition or deletion of chromosome in the individual. In case of trisomy of the $21^{st}$ chromosome causes Down's syndrome. This results in mental retardation and physical development is retarded as well. The palm of the individual is broad with characteristic palm crease.
Phenylketonuria is an inborn error of metabolism where the individual has reduced metabolism of the amino acid phenylalanine. Such mutation leads to mental retardation, with reduction in hair and skin pigmentation. It is a recessive autosomal disorder.
Haemophilia are X-linked recessive disorder. X chromosome is part of the sex chromosome. In haemophilia, the individual has delayed clotting time for blood which can be fatal.
Sickle cell anemia is a type of genetic blood disorder which is inherited from the parents. The person suffering from it develops an abnormal haemoglobin that leads to elongated and curved or sickle shaped RBC. Such condition occurs when the individual inherits two abnormal copies of gene for beta globin chain of haemoglobin from each parent. It is an autosomal recessive disorder.