Answer: helper T cells.
- A helper T cells
- B red blood cells
- C nerve cells
- D muscle cells
Correct answer: A. helper T cells
Explanation: HIV destroys helper T lymphocytes, weakening the immune response.
An antibody is Y-shaped, with two identical antigen-binding sites at the tips of the variable regions - each shaped to recognise one specific antigen - while the constant (Fc) region at the base is recognised by immune cells to trigger further responses.
Concept context
Innate and adaptive immunity, B cells, T cells, antibodies, vaccines, and immune disorders. Critical for NEET.