Plant nutrition and photosynthesis

Learning objectives

• Explain the inputs and products of photosynthesis.
• Connect leaf structures to their functions.
• Interpret limiting-factor evidence.

The big idea

Photosynthesis transfers light energy into chemical stores by making carbohydrates from carbon dioxide and water. Chlorophyll absorbs light, while mineral ions support other functions such as protein and chlorophyll production.

Leaves combine a broad surface, gas spaces, stomata and vascular tissue. Light intensity, carbon dioxide and temperature can limit the rate; changing one factor has little effect once another becomes limiting. Plants also respire, both in light and darkness.

Investigate and explain

Using the worked example as supplied data, predict the effect of changing one condition. Draw a labelled model, record your reasoning and identify a variable that would need controlling. No human, animal or microbial experiment is required.

No exact PhET model is claimed for this topic. Use diagrams and supplied-data reasoning instead.

Open the interactive investigation

Check your understanding