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Human Health and Disease — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Health and Disease2 Marks
Question
What does the term 'memory' of the Immune system mean?
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Answer

Acquired immunity is pathogen specific and is based on ‘memory’. When a pathogen attacks the body for the first time, the body gives a primary response which is of low intensity. When the pathogen strikes once again in future, the secondary response is more intensified. This happens because of the ‘memory’ of the immune system.

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