Antigen Z is found on pathogen Z, which can cause disease. Researchers measured antibody concentrations after people were exposed to antigen Z. The people in the later-exposure group had encountered the same antigen before.
| Days after exposure | First exposure (arbitrary units per mL) | Later exposure (arbitrary units per mL) |
|---|---|---|
| 0 | 4 | 6 |
| 3 | 12 | 150 |
| 6 | 40 | 420 |
| 9 | 100 | 500 |
Explain the difference between the antibody responses shown in the table and predict what is likely to happen to a person after later exposure to pathogen Z.
87 exam-style questions on Edexcel GCSE Biology 5.3 Immune system and medicines, covering 5.3.1 The specific immune system, 5.3.2 Response to immunisation, 5.3.3 Advantages and disadvantages of immunisation, 5.3.4 Antibiotics and bacterial infections, 5.3.5 Aseptic techniques in culturing, 5.3.6 Cross-sectional areas of cultures, 5.3.7 Stages of developing new medicines, and 5.3.8 Production of monoclonal antibodies. Each one has a worked solution and a mark scheme showing where the marks go.