Doctors carry out a glucose tolerance test on three people, A, B and C.
In a person without diabetes, the blood glucose concentration 2 hours after the drink is below 7.8 mmol per dm3\text{dm}^3dm3.
The Table shows the results.
Table
| Person | Blood glucose concentration after 2 hours in mmol per dm3\text{dm}^3dm3 | Blood insulin concentration after 2 hours in arbitrary units |
|---|---|---|
| A | 5.5 | 20 |
| B | 15.0 | 2 |
| C | 13.5 | 45 |
Identify which person, B or C, has type 1 diabetes.
Explain your answer using data from the Table.
Explain why person C's blood glucose concentration is high even though their insulin concentration is high.
Person B is treated with insulin injections. Person C is first advised to change their diet and do more exercise.
Explain why person C is not usually given insulin injections as their first treatment.
72 exam-style questions on OCR GCSE Biology 3.3 Maintaining internal environments, covering 3.3.1 Importance of a constant internal environment, 3.3.2 The skin and body temperature, 3.3.3 Insulin and blood sugar, 3.3.4 Glucagon and blood sugar, 3.3.5 Type 1 and type 2 diabetes, 3.3.6 Osmotic changes in body fluids, 3.3.7 Kidneys and water balance, 3.3.8 Structure of the kidney and tubule, 3.3.9 ADH and kidney tubule permeability, and 3.3.10 Responses to temperature and osmotic challenges. Each one has a worked solution and a mark scheme showing where the marks go.