Question

White blood cells (leucocytes) that are non-specific killers of microbes are

• A. Phagocytes
• B. B-cells
• C. killer T-cells
• D. helper T-cells

Answer 1

Answer: (A)

Phagocytes

A- Monocytes are the largest of the white blood cells. Macrophages are monocytes that are present in nearly all tissue. They digest cells and pathogens by engulfing them in a process called phagocytosis.

B- B cells are a class of white blood cell known as a lymphocyte. B cells produce specialized proteins called antibodies to counter pathogens. Antibodies help to identify pathogens by binding to them and targeting them for destruction by other immune system cells.

C- Distinguish infected or cancerous cells from normal body cells and attack cells that are not identified as body cells.

D- Assist in the production of antibodies by B cells and help to activate cytotoxic T cells and macrophages.

So, the correct option is 'phagocytes'.