An epidemiologist is evaluating two clinical interventions to maintain public health during an outbreak of a toxin-producing bacterium:
Which statement correctly compares the immunological mechanisms and outcomes of these two interventions?
Intervention X provides passive immunity because the toxoid is an inactive antigen, whereas Intervention Y provides active immunity because the monoclonal antibodies actively neutralize the toxin.
Intervention X stimulates the host's B lymphocytes to undergo clonal selection and produce memory cells, offering long-term protection, whereas Intervention Y provides immediate, temporary protection because the injected antibodies do not stimulate the production of memory cells.
Intervention X relies on cytotoxic T lymphocytes to destroy infected host cells directly for immediate protection, whereas Intervention Y depends on the monoclonal antibodies multiplying within the lymphatic system to provide lifelong immunity.
Both interventions induce active immunity, but Intervention X is preferred for immediate outbreak control because the toxoid stimulates faster clonal expansion than pre-formed monoclonal antibodies.
97 exam-style questions on OCR GCSE Biology 6.3 Monitoring and maintaining health, covering 6.3.1 Health and disease, 6.3.2 Interactions between diseases, 6.3.3 Spread of communicable diseases, 6.3.4 Common infections and diseases, 6.3.5 Physical plant defence responses, 6.3.6 Chemical plant defence responses, 6.3.7 Detecting and identifying plant diseases, 6.3.8 White blood cells and platelets, 6.3.9 Non-specific defence systems, 6.3.10 The immune system, 6.3.11 Monoclonal antibodies, 6.3.12 Vaccines and medicines, 6.3.13 Aseptic techniques, 6.3.14 Discovery and development of new medicines, 6.3.15 Causes of non-communicable diseases, 6.3.16 Treatments for cardiovascular disease, 6.3.17 Lifestyle factors and non-communicable diseases, 6.3.18 Cancer, 6.3.19 Stem cells in medicine, 6.3.20 Gene technology in medicine, and 6.3.21 The human genome and medicine. Each one has a worked solution and a mark scheme showing where the marks go.