This exam focus covers Exam Focus within Adaptive Immunity and Antibodies for GCSE Biology. Specific immune responses, antibody production, lymphocytes, memory cells It is section 16 of 18 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Topic position
Section 16 of 18
Practice
20 questions
Recall
25 flashcards
Exam Focus
Very Frequently ExaminedAdaptive immunity is one of the highest-mark topics in AQA Unit 5 and underpins questions on vaccination (Topic 19) and monoclonal antibodies (Topic 21). Understanding it deeply unlocks marks across multiple topics.
- 4-mark B cell response question: Antigen detected → specific B cell selected (clonal selection) → B cell divides (clonal expansion) → plasma cells produce antibodies → memory B cells formed. All five steps needed.
- 5-6 mark primary vs secondary response: Must include: lag time difference, antibody level comparison, mechanism (memory cells), and why secondary response prevents disease. Include a named example.
- Antibody function (2 marks): Tag pathogens for phagocytosis (opsonisation) AND neutralise toxins/prevent binding to host cells. Never say antibodies "kill" pathogens — they don't.
- Higher only — B vs T lymphocytes: Know that B cells produce antibodies (humoral immunity) and T cells kill infected cells (cell-mediated). Know that HIV destroys helper T cells. These appear in higher-tier 4-mark questions.
Common mark losses: Saying antibodies kill pathogens directly (they tag them). Confusing plasma cells with memory cells (plasma cells make antibodies; memory cells provide future protection). Describing the secondary response as slower than the primary.