How does a vaccine give protection?
Answer and explanation
Correct answer: A. Harmless antigens stimulate memory cell formation
- Step 1: Vaccines expose the immune system to antigens without causing disease.
- Step 2: The immune system forms memory cells, giving active immunity.
Answer
Harmless antigens stimulate memory cell formation.
Why not the others: It contains antibodies that kill the pathogen: this gives passive immunity. It contains live, harmful pathogens: vaccines are weakened or inactive. It destroys the pathogen directly with chemicals: vaccines work through the immune system.
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