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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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True about active immunity
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The correct answer is  When B cells and T cells are activated by a pathogen, memory B-cells and T- cells develop, and the primary immune response results. Throughout the lifetime of an animal these memory cells will "remember" each specific pathogen encountered, and are able to mount a strong secondary response, if the pathogen is detected again. Ref: Ananthanarayan & Panikers textbook of microbiology 9th edition pg.no. : 81-84