Answer: Digesting the cell walls of bacteria.
- A Producing antibodies against incoming airborne pathogens
- B Digesting the cell walls of bacteria
- C Activating cytotoxic T cells at mucosal surfaces
- D Triggering phagocytosis by resident neutrophils
Correct answer: B. Digesting the cell walls of bacteria
Explanation: Lysozyme is an enzyme that hydrolyzes peptidoglycan in bacterial cell walls, causing bacteria to burst (lysis). It provides non-specific antimicrobial protection in tears, saliva, mucus, and breast milk.
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.