Question

(b) What is a ‘vaccine’? Explain the principle on which it works.

Hint:

Vaccines mimic infections, enabling the immune system to recognize and combat real pathogens effectively in the future.

Answer 1

- Definition: A vaccine is a biological preparation that provides active immunity against specific diseases. 
- Principle: Vaccines work by stimulating the immune system to produce antibodies against the disease-causing agent without causing the disease itself. This enables the body to fight the actual pathogen in the future.