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Explain How Does Vaccine Work? - Science

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Question

Explain how does vaccine work?

Short/Brief Note
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Solution

A vaccine is a small quantity of a weakened antigen that is injected into the body of an individual. Once the antigen gets into the body of a healthy person, his/her body synthesises antibodies against the antigen. Once the body encounters an infectious antigen, it develops a memory; and when that antigen enters that body again, a large amount of antibodies is secreted by the body to destroy the antigen. Hence, it prevents the disease from occurring.

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Chapter 5: Why Do We Fall Ill - Short Questions Answer 1 (Carrying 2 Marks) [Page 308]

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P S Verma and V K Agarwal Biology [English] Class 9
Chapter 5 Why Do We Fall Ill
Short Questions Answer 1 (Carrying 2 Marks) | Q 14 | Page 308

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