The yellowish fluid secreted by mother during initial days of lactation has abundant:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → IgA
Option (1) IgA — Correct. The yellowish fluid is colostrum. Its IgA gives the baby passive immunity: ready-made antibodies from the mother.
Option (2) IgM — Incorrect. IgM is one of the types of antibodies in the blood. It is not the antibody colostrum is rich in.
Option (3) IgE — Incorrect. IgE is the antibody made in an allergy. It makes mast cells release histamine and serotonin.
Option (4) IgG — Incorrect. IgG is the commonest antibody of the blood. The foetus gets some antibodies through the placenta, but the antibody abundant in colostrum is IgA.
NCERT Extract:
Active and Passive Immunity – “When ready-made antibodies are directly given to protect the body against foreign agents, it is called passive immunity. … The yellowish fluid colostrum secreted by mother during the initial days of lactation has abundant antibodies (IgA) to protect the infant. The foetus also receives some antibodies from their mother, through the placenta during pregnancy. These are some examples of passive immunity.”