Explain how the structure of a leaf is adapted to allow efficient photosynthesis.

Eduqas GCSE Biology — 1.5.1 Plant structure and function · Explain · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

Model answer (4 marks)

Leaves are broad, giving a large surface area to absorb light.
Stomata on the leaf surface allow CO₂ to enter and O₂ to leave.
The epidermis is thin, so light penetrates easily.
Chloroplasts in the mesophyll cells contain chlorophyll to capture light energy for photosynthesis.

Examiner tips

Use the exact terms: broad leaf, large surface area, stomata, CO₂, O₂, chloroplasts, chlorophyll.
Show the link between structure and function – e.g. large area → more light absorption.
Mention the role of stomata in gas exchange.
Keep the answer concise and to the point.

Common mistakes

Confusing stomata with other pores; not specifying CO₂/O₂ exchange.
Omitting the mesophyll or chloroplast detail.
Using vague phrases like ‘good for photosynthesis’ instead of specific adaptations.

Mark scheme (4 marks)

Leaves are broad / have a large surface area
To absorb more light for photosynthesis
Leaves contain stomata which allow carbon dioxide to enter (and oxygen to leave)
Chloroplasts (containing chlorophyll) are found in leaf cells to absorb light energy

Key terms in this question

photosynthesis