A culture of photosynthetic bacteria is supplied continuously with water and carbon dioxide. The temperature is kept constant.
A sensor measures the volume of oxygen released during three consecutive periods.
| Time period in minutes | Light condition | Volume of oxygen released in cm3\text{cm}^3cm3 |
|---|---|---|
| 0–5 | light | 2.4 |
| 5–10 | dark | 0.0 |
| 10–15 | light | 2.3 |
Describe the pattern in the volume of oxygen released.
Explain these results and what happens to glucose production by the bacteria in the light and in the dark. Use your knowledge of the two stages of photosynthesis.
117 exam-style questions on OCR GCSE Biology 1.4 Photosynthesis, covering 1.4.1 Photosynthesisers as biomass producers, 1.4.2 Factors affecting the rate of photosynthesis, and 1.4.3 Limiting factors in photosynthesis. Each one has a worked solution and a mark scheme showing where the marks go.