Photosynthesis takes place in two stages.
In stage 1, light energy is used to split water molecules.
In stage 2, carbon dioxide is used to make glucose.
Name the sub-cellular structure where both stages take place.
Explain why photosynthesis is described as an endothermic reaction.
A leaf receives 25 000 kJ25\,000\ \text{kJ}25000 kJ of light energy in one day. Only 2% of this energy is used in photosynthesis.
Calculate the amount of energy used in photosynthesis.
Photosynthetic organisms are the main producers of food for life on Earth.
Explain why.
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.