Question

Colostrum is very essential to impart immunity to the newborn infants because it contains

• A. Immunoglobulin A
• B. Natural killer cells
• C. Monocytes
• D. Macrophages

Answer 1

The correct option is A

Immunoglobulin A

The correct option is A.

The explanation for the correct option:

• Colostrum is the yellowish fluid that is secreted by the mother after the birth of the baby and on the initial days of lactation. This is very essential for a newborn as it supplies plentiful immunoglobulin A (IgA) that provides immunity.
• It is an example of naturally acquired immunity. It is essential because the immune system of newborns is not developed and immunity acquired from colostrum provides protection.

The explanation for incorrect options:

Option B:

• Natural killer cells are one kind of cytotoxic lymphocyte cell and have a critical role in the innate immune system for combatting infectious pathogens.
• They are mainly involved in the antiviral and anti-tumor response. NK-cells are not present in colostrum.

Option C:

• Monocytes are white blood cells (lymphocytes). Their function is to find and destroy pathogenic viruses, bacteria, fungi, and protozoa.
• Monocytes bring other WBCs to help in treating injury and preventing infections. They are part of cell-mediated immunity.

Option D:

• Macrophages are antigen-presenting cells (APCs) and have an essential role in the detection, phagocytosis, and destruction of pathogenic bacteria and other organisms.
• Their function is to present antigens to T-cells and start off inflammation by activating the secretion of cytokines that activate other immune cells. They are part of cell-mediated immunity.

Final answer: So, colostrum is very essential to impart immunity to newborn infants because it contains abundant immunoglobulin A (IgA).