Energy Pyramid

Class 10 Science: our environment (10% law)

Follow energy up a food chain from grass to an eagle. Why is so little left at the top?

Words to know

Trophic level: Each step in a food chain: producers, herbivores, carnivores.
10% law: Only about 10% of energy passes to the next level.
Producer: A green plant that makes food from sunlight.
Food chain: Who eats whom, showing how energy flows.

Quick check

Answer 3 questions to check what you learned.

1. With the 10% law, 1000 kJ in plants gives a herbivore about…

2. Where does most of the energy at each level go?

3. Why are food chains usually short (3–4 levels)?

Try at home

Write a food chain from your area (for example grass → goat → human). Start with 1000 units of energy in the grass. How much reaches you with the 10% law?

Next, try a full lab

Food Web Predator and Prey All Class 9–10 labs