The process used by producers to make their own food via a series of chemical reactions.

A measure of how much change occurs per unit of time.

A condition that when in short supply slows down or limits the rate of photosynthesis.

A biological catalyst that speeds up a chemical reaction without itself being used up.

The conditions where maximum rate of reaction occurs.

Factors affecting the rate of photosynthesis

Combined science

Pupils learned about ways in which the human body maintains a constant internal environment in response to internal and external change, including changes in temperature and water balance.

This unit explores factors affecting photosynthesis rates and focuses on planning and conducting experiments. It includes selecting techniques, accurate measurements, data analysis, and evaluating methods to improve reliability and suggest further investigations.

Photosynthesis: factors affecting the rate

a condition that has no effect on the rate of photosynthesis

a condition that slows down the rate of photosynthesis when in short supply

a condition that speeds up photosynthesis

a factor that always increases the rate of photosynthesis

What is a limiting factor in photosynthesis?

What happens to the rate of photosynthesis at very high temperatures?

Enzymes involved in photosynthesis become more effective at high temperatures.

High temperatures increase the availability of water to the plant.

Enzymes involved in photosynthesis can denature, reducing their effectiveness.

High temperatures increase the rate of photosynthesis.

Why does the rate of photosynthesis decrease at high temperatures?

 it decreases the rate after a certain point

it increases the rate until an optimum level is reached

How does carbon dioxide concentration affect the rate of photosynthesis?

At carbon dioxide concentrations above the optimum, what limits the rate of photosynthesis?

Which of the following are reactants for photosynthesis?

carbon dioxide + oxygen → glucose + water

carbon dioxide + water → glucose + oxygen

glucose + oxygen → carbon dioxide + water

water + glucose → carbon dioxide + oxygen

What is the correct summary word equation for photosynthesis?

Where in the plant cell does photosynthesis occur?

6CO₂ + 12H₂O → C₆H₁₂O₆ + 6O₂ + 6H₂O

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

 C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O

What is the correct summary symbol equation for photosynthesis?

It increases activity up to an optimum point.

What effect does temperature have on enzyme activity?

Starter Quiz