Some cells in an aquatic animal move ions across their cell membranes by active transport.
A scientist compares equal numbers of these cells in samples A and B. The cells are kept for 30 minutes in identical insulated containers. Each sample is supplied with excess glucose and oxygen.
| sample | volume of oxygen used in 30 minutes / cm3\text{cm}^3cm3 | temperature increase / ∘C^{\circ}\text{C}∘C | mean number of mitochondria per cell |
|---|---|---|---|
| A | 9.6 | 1.8 | 160 |
| B | 2.4 | 0.4 | 40 |
Calculate how many times greater the volume of oxygen used by sample A is than the volume used by sample B.
The scientist concludes that the cells in sample A can move ions by active transport at a higher rate than the cells in sample B.
Explain how all the results support this conclusion.
98 exam-style questions on Edexcel GCSE Biology 8.3 Respiration, covering 8.3.1 Aerobic and anaerobic respiration. Each one has a worked solution and a mark scheme showing where the marks go.