Advanced Topics
In a nutshell: Food chains show how energy moves through living things in ecosystems.
## How Do Living Things Get Energy?
All living things need energy, and they get it from food! A **food chain** shows how energy passes from one living thing to another.
- Plants use sunlight to make food.
- Animals eat plants (or other animals) to get energy.
## What Is an Ecosystem?
An ecosystem is all the living and non-living things in a place and how they interact. Every part of an ecosystem depends on the others, like a team working together.
## Why Is This Important?
If one part of a food chain or ecosystem is changed, it can affect everything else!
Examples
- A rabbit eats grass, and a fox eats the rabbit—energy moves from plants to animals.
- A pond ecosystem with plants, fish, insects, and birds working together.
Key terms
- Ecosystem
- A community of living and nonliving things that work together.
- Food Chain
- The order in which living things get energy from food.