Answer: Innate immunity.
- A Innate immunity
- B Acquired immunity
- C Active immunity
- D Passive immunity
Correct answer: A. Innate immunity
Explanation: Innate immunity is inborn and non-specific, giving the same broad defence against all pathogens.
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.