Food Webs and Energy Flow
Energy flows through ecosystems from the Sun to producers and then to consumers, with energy lost at each stage.
▶ Interact
Play with the controls to see the idea in action.
📘 Learn
Energy flows through ecosystems from the Sun to producers and then to consumers, with energy lost at each stage.
- Only about 10 percent passes on
- Decomposers recycle nutrients
- Apex predators are at the top
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Food Webs and Energy Flow?
Within Earth & Environmental Science, which covers our planet, its resources and ecosystems, and how people can protect the environment, this topic explains Food Webs and Energy Flow. Earth and environment topics show how the planet’s systems shape landscapes, climate and life, with models that make these processes visible.
Check that you can explain Food Webs and Energy Flow in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Food Webs and Energy Flow helps you explain the environment around you and weigh up how people can protect it.
Food Webs and Energy Flow in detail
A food chain shows who eats whom, starting with producers (plants and algae), then primary consumers (herbivores), secondary and tertiary consumers (carnivores), with decomposers breaking down dead matter. Food webs connect many chains, showing that most species have several food sources.
Energy flows one way: from the Sun, through producers, to consumers, with only about 10% passing to the next level, as the rest is lost as heat or in waste. This is why food chains are short and why there are fewer top predators. Pyramids of numbers, biomass and energy show this. Removing one species can affect the whole web.
How the interactive helps you understand Food Webs and Energy Flow
Watch the population model in the interactive. Use any sliders or buttons it offers to change the values and see how the population model 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 Food Webs and Energy Flow.
Real-life uses and examples
- Use a diagram of Food Webs and Energy Flow to describe the steps of a process in order.
- Discuss how human activity changes Food Webs and Energy Flow, using a named example.
- Explain how Food Webs and Energy Flow affects the landscape or climate near you.
Common mistakes to avoid
- Describing a process without the timescale it works over.
- Presenting one cause as the only cause of an environmental change.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Food Webs and Energy Flow
What is Food Webs and Energy Flow?
Energy flows through ecosystems from the Sun to producers and then to consumers, with energy lost at each stage.
What are the most important points about Food Webs and Energy Flow?
The main points are: Only about 10 percent passes on; Decomposers recycle nutrients; Apex predators are at the top.
Why is Food Webs and Energy Flow useful?
Understanding Food Webs and Energy Flow helps you explain the environment around you and weigh up how people can protect it.
How can I practise Food Webs and Energy Flow?
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 Food Webs and Energy Flow?
Related topics in Earth & Environmental Science include Endangered Species and Conservation, Deserts and Grasslands, Coral Reefs.