question_answer

Directions : (41 - 45)

Read the passage given below and answer the following questions.

Thalassemia is also an autosome linked recessive i.e., chromosome 11 and 16, blood disease transmitted from parents to the offspring when both the partners are unaffected carrier for the gene or heterozygous. The defect could be due to either mutation or deletion which ultimately results in reduced rate of synthesis of one of the globin chains that make up haemoglobin. This causes the formation of abnormal haemoglobin molecules resulting into anaemia which is characteristic of the disease. Thalassemia can be classified according to which chain of the haemoglobin molecule is affected. Thalassaemia is a genetic defect, originated in Mediterranean region by their mutation or deletion. In thalassaemia too few globin's are synthesised whereas in sickle cell anaemia there is a synthesis of incorrectly functioning globin. Thalassemia's are a group of disorders caused by defects in the synthesis of globin polypeptide. Absence or reduced synthesis of one of the globin chains results in an excess of the other. In this situation free globin chains, which are insoluble, accumulate inside the red cells and form precipitates which damage the cell, causing cell lysis and resulting in anemia. It is common in Mediterranean, Middle East, Indian subcontinent and in south east Africa.

Thalassemia is due to:

A) Chromosome number 11.

B) Chromosome number 12.

C) Chromosome number 13.

D) Chromosome number 11 and 16.