A student adds sodium hydrogencarbonate solution to the water around some pondweed. The rate of photosynthesis increases. Which statement explains why?
It releases oxygen, which the pondweed uses to make glucose.
It raises the temperature of the water around the pondweed.
It is a source of glucose, which the pondweed absorbs.
It releases carbon dioxide, which is a reactant in 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.