Question:
(b) What is a ‘vaccine’? Explain the principle on which it works.
(b) What is a ‘vaccine’? Explain the principle on which it works.
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Vaccines mimic infections, enabling the immune system to recognize and combat real pathogens effectively in the future.
Updated On: Jan 13, 2026
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Solution and Explanation
- 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.
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