Energy pyramids

What is an energy pyramid?

A diagram showing the amount of available energy at each trophic level.

Which trophic level has the most energy?

Producers at the bottom.

What happens to energy as you move up an energy pyramid?

The amount of available energy decreases.

Why does energy decrease at higher trophic levels?

Organisms use energy for life processes such as movement, growth and respiration, and some energy is released as heat.

What is the approximate 10% rule?

About 10% of the energy at one trophic level is transferred to the next trophic level.

Why are there usually fewer top predators than producers?

There is less available energy at higher trophic levels, so ecosystems can support fewer organisms.

What happens to energy that isn't transferred to the next trophic level?

Much of it is used by the organism or released into the environment as heat.