The Water Cycle
The water cycle is the continuous movement of water through evaporation, condensation, precipitation and run-off.
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Play with the controls to see the idea in action.
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The water cycle is the continuous movement of water through evaporation, condensation, precipitation and run-off.
- The Sun powers the cycle
- Clouds form by condensation
- Water returns by rivers and groundwater
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is The Water Cycle?
Within Biology, which covers cells, the human body, genetics, evolution, plants and ecosystems: the science of living things, this topic explains The Water 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 Water 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 Water Cycle helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
The Water Cycle in detail
The water cycle describes the continuous movement of water between the Earth's surface and the atmosphere. Energy from the Sun causes evaporation from oceans, lakes and rivers, and transpiration from plants. Water vapour rises, cools and condenses to form clouds, then falls as precipitation (rain, snow, hail).
Water then runs into rivers or soaks into the ground, and returns to the sea, and the cycle repeats. It provides fresh water for living things and shapes weather and landscapes. Human activities such as building dams and cutting down forests can alter the cycle, and water supply is a growing concern.
How the interactive helps you understand The Water 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 Water Cycle.
Real-life uses and examples
- Explain how The Water Cycle helps a living thing stay alive, using a plant or animal example.
- Connect The Water Cycle to health, food and medicine in everyday life.
- Use The Water Cycle to interpret a diagram, graph or microscope image from a practical.
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 Water Cycle
What is The Water Cycle?
The water cycle is the continuous movement of water through evaporation, condensation, precipitation and run-off.
What are the most important points about The Water Cycle?
The main points are: The Sun powers the cycle; Clouds form by condensation; Water returns by rivers and groundwater.
Why is The Water Cycle useful?
Understanding The Water 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 Water 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 Water Cycle?
Related topics in Biology include Adaptation, Sampling Ecosystems, Eutrophication.