Prostate cancer cells release a protein called PSA into the blood. Monoclonal antibodies that are complementary to PSA can be used to test for PSA in a blood sample.
Monoclonal antibodies can also be used to treat some types of cancer.
Scientists tested 1000 men for PSA. They then found out which of the men had prostate cancer.
The Table shows the results.
Table
| PSA test result | Number of men with prostate cancer | Number of men without prostate cancer |
|---|---|---|
| positive | 72 | 150 |
| negative | 28 | 750 |
Describe what is meant by cancer.
A drug that kills cells can be attached to monoclonal antibodies that bind to an antigen found only on cancer cells.
Explain why this treatment causes fewer side effects than giving the same drug on its own.
Calculate the percentage of men with prostate cancer who had a positive PSA test.
A doctor says that the PSA test alone should not be used to decide whether a man has prostate cancer.
Use data from the Table to explain why.
181 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.