Infection & ResponseTopic Summary
Knowledge Organiser
Part of Adaptive Immunity and Antibodies — GCSE Biology
This topic summary covers Knowledge Organiser within Adaptive Immunity and Antibodies for GCSE Biology. Specific immune responses, antibody production, lymphocytes, memory cells It is section 17 of 18 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 17 of 18
Practice
20 questions
Recall
25 flashcards
Knowledge Organiser
Key Cells
- B lymphocyte — recognises antigen, divides, forms plasma cells and memory B cells
- Plasma cell — secretes thousands of antibodies per second
- Memory B cell — long-lived, enables fast secondary response
- Helper T cell — coordinates immune response, activates B cells
- Cytotoxic T cell — kills infected body cells directly
- Macrophage — presents antigens to activate T cells
Key Processes
- Clonal selection — antigen selects specific B cell with matching receptor
- Clonal expansion — selected B cell divides repeatedly
- Antibody production — plasma cells secrete specific antibodies
- Primary response — slow (5-10 days), low antibodies, creates memory
- Secondary response — fast (1-3 days), high antibodies, prevents disease
Common Marks Lost
- Saying antibodies kill pathogens (they tag them for phagocytes)
- Confusing plasma cells (make antibodies) with memory cells (future protection)
- Saying secondary response is slower (it is much faster)
- Not explaining WHY secondary response is faster (memory cells)
- Using antibiotics for viral infections in exam scenarios