Explain why leaves are well adapted for photosynthesis to occur efficiently.
Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).
Model answer (4 marks)
Leaves have a large surface area, allowing more light to be absorbed and increasing the amount of light available for photosynthesis.
Leaves contain chlorophyll in chloroplasts, which absorbs light energy and converts it into chemical energy.
Leaves have stomata, pores that permit CO₂ to enter the leaf and O₂ to exit, ensuring the gases required for the reaction are available.
These features together maximise light capture, energy conversion and gas exchange, making leaves highly efficient for photosynthesis.
Leaves contain chlorophyll in chloroplasts, which absorbs light energy and converts it into chemical energy.
Leaves have stomata, pores that permit CO₂ to enter the leaf and O₂ to exit, ensuring the gases required for the reaction are available.
These features together maximise light capture, energy conversion and gas exchange, making leaves highly efficient for photosynthesis.
Examiner tips
- Use the exact terms: surface area, chlorophyll, stomata. Explain the function of each feature. Show the link between structure and function. Keep the answer concise and directly address the question.
Common mistakes
- Confusing stomata with other leaf structures. Omitting the role of chlorophyll. Failing to mention the importance of CO₂ and O₂ exchange. Writing a generic description of leaves without linking to photosynthesis.
Mark scheme (4 marks)
- Leaves have a large surface area
- to absorb more light / maximise light absorption for photosynthesis
- Leaves contain chlorophyll (in chloroplasts) which absorbs light energy
- Leaves have stomata / pores that allow carbon dioxide to enter (and oxygen to leave)
Key terms in this question
Related
- All WJEC GCSE Biology (Wales) revision notes →
- How to answer a "Explain" question →
- Decode the mark scheme abbreviations →
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