Question

Erythroblastosis fetalis is related to
(a) Blood group
(b) Rh factor
(c) Infectious disease
(d) All of these

Answer 1

Hint: Human blood groups are different types of erythrocytes phenotypes which is due to the presence of genetically controlled antigens and antibodies. Most widely used blood groups are the ABO and Rh type.

Complete answer:
Rh factor is responsible for erythroblastosis fetalis which destroys erythrocyte of the foetus. This condition takes place due to incompatibility between the Rh factor of mother and foetus during pregnancy.
In the first pregnancy, Rh factor transfusion between mother and foetus causes no harm because of the presence of antibodies. But in case of second pregnancy when transfusion takes place the mother start preparing antibodies which if leak into the blood of foetus can destroy the foetal RBC because both Rh factor of mother and foetus consist of different Rh factors like Rh-positive in a foetus and Rh-negative in mother, Rh-positive consist of Rh factor while Rh negative does not consist of Rh factor. Erythroblastosis foetal leads to severe anaemia and jaundice to the baby, in severe cases it can be fatal. It can be prevented by administration of anti-Rh antibodies to the mother immediately after delivery of the first child.

Additional Information: Rh blood group was discovered by Landsteiner and Weiner in 1940 which is a type of protein on the surface of blood corpuscles. It was first discovered in case of a rhesus monkey that's why it is named as Rh. 80-90 per cent of human beings are Rh-positive. Formation of Rh protein controlled by a dominant gene, therefore RR and Rr are positive and rr is a negative factor.
So, the correct answer is the Rh factor.

Note: Blood group is identified by agglutination which shows clumping. If samples show agglutination with anti-A then blood group is A, if show agglutination with anti-B then B and if show agglutination with both anti-A and anti-B then blood group will be and if does not show agglutination then blood group will be O.