Question

Name the antibody most abundant in human colostrum.

• A. IgG
• B. IgM
• C. IgA
• D. IgE

Hint:

IgA is mainly found in secretions like saliva, tears, and milk, where it plays a key role in mucosal immunity.

Answer 1

The Correct Option is C

Concept:
Colostrum is the first milk produced by the mother immediately after childbirth. It is rich in antibodies that provide passive immunity to the newborn. Among all immunoglobulins, Immunoglobulin A (IgA) is the most abundant in colostrum.

Step 1: Understand the function of colostrum.
Colostrum protects the newborn against infections, especially in the early days when the infant's immune system is not fully developed.

Step 2: Role of IgA.
IgA protects mucosal surfaces such as the gastrointestinal tract by preventing pathogen attachment.

Step 3: Conclusion.
Thus, IgA is the predominant antibody in colostrum. \[ \boxed{\text{IgA}} \]