Edexcel IGCSE Biology · Spec 2.62-2.64B
The Immune System
How phagocytes and lymphocytes fight pathogens, why antibodies are specific, and how vaccines give immunity.
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The Immune System
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Spec 2.62-2.64B
What you need to know
- Describe how phagocytes destroy pathogens
- Describe how lymphocytes make antibodies
- Explain immunity and how vaccines work
Active recall
Quick check
Answer each question before opening the answer.
How do phagocytes and lymphocytes protect the body?
Phagocytes engulf and digest pathogens; lymphocytes produce antibodies against specific antigens.
How does a vaccine give immunity?
It contains a dead/weakened pathogen (antigen); the body makes antibodies and memory cells, so it responds quickly if infected later.
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