A student investigates the effect of temperature on the rate of photosynthesis in pondweed.
She puts pondweed in water baths at different temperatures. She collects the oxygen given off in 5 minutes.
The Table shows her results.
Table
| Temperature in ∘C^{\circ}\text{C}∘C | Volume of oxygen given off in 5 minutes in cm3\text{cm}^3cm3 |
|---|---|
| 10 | 0.8 |
| 20 | 1.9 |
| 30 | 3.4 |
| 40 | 2.1 |
| 50 | 0.3 |
Calculate the rate of oxygen production at 30 ∘C30\ ^{\circ}\text{C}30 ∘C.
Give your answer in cm3\text{cm}^3cm3 per minute.
Explain why the volume of oxygen given off increases between 10 ∘C10\ ^{\circ}\text{C}10 ∘C and 30 ∘C30\ ^{\circ}\text{C}30 ∘C.
Explain why the volume of oxygen given off decreases between 30 ∘C30\ ^{\circ}\text{C}30 ∘C and 50 ∘C50\ ^{\circ}\text{C}50 ∘C.
The student says:
'The optimum temperature for photosynthesis in pondweed is 30 ∘C30\ ^{\circ}\text{C}30 ∘C.'
Suggest how she could find the optimum temperature more precisely.
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.