Concept 8 of 9Foundation

Food chains and food webs

A food chain shows who eats whom, in order. Arrows point in the direction of ENERGY FLOW.

Example: Grass → Grasshopper → Frog → Snake → Eagle.

Three roles in any chain:

Producers (plants): make their own food via photosynthesis. Start of every chain.
Consumers: eat other organisms. Primary (herbivores) → Secondary (carnivores) → Tertiary (top predators).
Decomposers (fungi, bacteria): break down dead matter, recycle nutrients to soil.

A food web is many food chains connected together — a more realistic picture of ecosystems.

Example

If snakes are killed off, frog population grows → grasshoppers decline → grass thrives but eagles starve. Removing any link disrupts everything.

💡 Tip:All food chains start with the Sun (via producers). Energy flows UP but decreases at each step (only ~10% passes on).