The concentration of oxygen in the air is lower at high altitude than at sea level.
The Table shows the concentration of oxygen in the air in the alveoli and in the blood arriving at the lungs, for one person at sea level and at high altitude.
Table
| Location | Concentration of oxygen in the air in the alveoli in arbitrary units | Concentration of oxygen in the blood arriving at the lungs in arbitrary units |
|---|---|---|
| sea level | 100 | 40 |
| high altitude | 60 | 30 |
Calculate the percentage decrease in the concentration difference of oxygen between the alveoli and the blood when the person moves from sea level to high altitude.
Use Fick's law to explain the effect of this change on the rate of oxygen diffusion into the blood.
When people first arrive at high altitude, their breathing rate increases.
Explain how this helps to increase the rate of oxygen diffusion into the blood.
42 exam-style questions on Edexcel GCSE Biology 8.1 Exchange surfaces and diffusion, covering 8.1.1 Introduction to exchange and transport, 8.1.2 Alveoli adapted for gas exchange, 8.1.3 Factors affecting rate of diffusion, and 8.1.4 Rate of diffusion using Fick's law. Each one has a worked solution and a mark scheme showing where the marks go.