Emergency response trainees remained seated during a simulation. An unexpected warning alarm sounded. Researchers measured the mean blood adrenaline concentration and mean heart rate of the same trainees before the alarm and two minutes after it started.
| Time of measurement | Mean blood adrenaline concentration in nmol dm⁻³ | Mean heart rate in beats per minute |
|---|---|---|
| Before the alarm | 0.18 | 67 |
| Two minutes after the alarm started | 1.08 | 97 |
Explain how the results support the conclusion that adrenaline contributed to the change in mean heart rate.
Explain how the change in mean heart rate could allow energy to be released more quickly if the trainees then had to run.
89 exam-style questions on Edexcel GCSE Biology 7.1 Hormones and coordination, covering 7.1.1 Endocrine glands and hormone transport, 7.1.2 Adrenalin and fight or flight, and 7.1.3 Thyroxine and negative feedback. Each one has a worked solution and a mark scheme showing where the marks go.