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.

Photosynthesis and limiting factors

Biology

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

it enhances the rate of photosynthesis when in short supply

it slows down or limits the rate of photosynthesis when in short supply

What does it mean when a factor is described as a limiting factor?

Which of the following are not limiting factors of photosynthesis?

the rate of photosynthesis no longer increases

the rate of photosynthesis increases indefinitely

What occurs when light intensity reaches optimum levels in photosynthesis?

temperature has no effect on the rate of photosynthesis

the rate increases with temperature until enzymes denature

the rate remains constant with temperature changes

What is the relationship between temperature and the rate of photosynthesis?

Which of the following is most likely to be limiting the rate of photosynthesis at point A of the graph?

the rate is limited by CO₂ concentration

CO₂ concentration has a greater effect on the rate than temperature

the rate is unaffected by CO₂ concentration

Which of the following can be concluded from this graph?

What is the main function of chloroplasts in plant cells?

Which gas is essential for photosynthesis?

What is the chemical formula for glucose?

Which part of the plant leaf contains the most chloroplasts?

How does carbon dioxide enter the plant leaves?

What is the main product of photosynthesis?

This lesson will be removed by end of Summer Term 2025.

Photosynthesis and limiting factors

Lesson outcome

This lesson will be removed by end of Summer Term 2025.