During two operations carried out under the same conditions, patients A and B begin to lose energy to the surroundings. As their core temperatures fall, the smooth muscle in the skin arterioles of patient B contracts less strongly than that of patient A. All their other thermoregulatory responses are the same.
| patient | core temperature at start / ∘C^\circ\mathrm{C}∘C | core temperature after 30 minutes / ∘C^\circ\mathrm{C}∘C | mean diameter of skin arterioles after 30 minutes / mm |
|---|---|---|---|
| A | 37.0 | 36.7 | 0.024 |
| B | 37.0 | 36.1 | 0.036 |
Calculate how much greater the decrease in core temperature is for patient B than for patient A.
Using the information in the table, explain why the rate of enzyme-controlled reactions may be lower in patient B than in patient A after 30 minutes.
78 exam-style questions on Edexcel GCSE Biology 7.3 Homeostasis and thermoregulation, covering 7.3.1 Importance of a constant internal environment, 7.3.2 Importance of homeostasis, 7.3.3a Thermoregulation via the skin and hypothalamus, and 7.3.3b Vasoconstriction and vasodilation in thermoregulation. Each one has a worked solution and a mark scheme showing where the marks go.