During a swimming session, a swimmer's heart rate and stroke volume are measured immediately after the final length and again after 6 minutes of recovery.
| Time of measurement | Heart rate in beats per minute | Stroke volume in cm3\mathrm{cm^3}cm3 per beat |
|---|---|---|
| Immediately after the final length | 150 | 110 |
| After 6 minutes of recovery | 90 | 90 |
Use the equation:
cardiac output=stroke volume×heart rate \text{cardiac output}=\text{stroke volume}\times\text{heart rate} cardiac output=stroke volume×heart rateWhat is the percentage decrease in cardiac output during the 6 minutes of recovery?
51%51\%51%
104%104\%104%
40%40\%40%
18%18\%18%
67 exam-style questions on Edexcel GCSE Biology 8.2 Blood and circulation, covering 8.2.1 Structure and function of the blood, 8.2.2 Structure of blood vessels, 8.2.3 Structure of the heart and circulatory system, and 8.2.4 Cardiac output. Each one has a worked solution and a mark scheme showing where the marks go.