The Carbon Cycle
The carbon cycle moves carbon between the atmosphere, living things and the ground through processes such as photosynthesis, respiration and combustion.
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Play with the controls to see the idea in action.
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The carbon cycle moves carbon between the atmosphere, living things and the ground through processes such as photosynthesis, respiration and combustion.
- Plants take in carbon dioxide
- Respiration and burning release it
- Decay returns carbon to the soil
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is The Carbon Cycle?
Within Biology, which covers cells, the human body, genetics, evolution, plants and ecosystems: the science of living things, this topic explains The Carbon Cycle. Biology topics show how living things work, from the cell up to whole ecosystems, with models you can explore step by step.
Check that you can explain The Carbon Cycle in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding The Carbon Cycle helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
The Carbon Cycle in detail
The carbon cycle shows how carbon is recycled in nature. Carbon dioxide is removed from the air by photosynthesis, which turns it into carbohydrates in plants, and passed to animals when they eat. It returns to the air through respiration by plants, animals and decomposers and by combustion of fuels.
Over millions of years, dead organisms can become fossil fuels or limestone. Burning fossil fuels and deforestation add carbon dioxide faster than it is removed, contributing to global warming. Oceans also absorb carbon dioxide. Maintaining the balance depends on forests, plankton and sustainable human activity.
How the interactive helps you understand The Carbon Cycle
Watch the cycle in the interactive. Use any sliders or buttons it offers to change the values and see how the cycle responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of The Carbon Cycle.
Real-life uses and examples
- Use The Carbon Cycle to interpret a diagram, graph or microscope image from a practical.
- Structure a longer answer about The Carbon Cycle by moving from definition to example to consequence.
- Explain how The Carbon Cycle helps a living thing stay alive, using a plant or animal example.
Common mistakes to avoid
- Using everyday words, such as “energy” or “bad”, without their scientific meaning.
- Listing the steps of a process without saying how one step causes the next.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about The Carbon Cycle
What is The Carbon Cycle?
The carbon cycle moves carbon between the atmosphere, living things and the ground through processes such as photosynthesis, respiration and combustion.
What are the most important points about The Carbon Cycle?
The main points are: Plants take in carbon dioxide; Respiration and burning release it; Decay returns carbon to the soil.
Why is The Carbon Cycle useful?
Understanding The Carbon Cycle helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
How can I practise The Carbon Cycle?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to The Carbon Cycle?
Related topics in Biology include Decomposers and Decay, Population Dynamics, Biodiversity and Conservation.