Trophic Levels (Edexcel IGCSE Biology)

Revision Note

Trophic Levels

  • The trophic level is the level occupied by an organism within a food chain or food web:

Level

Organisms

Energy transfer

First trophic level

Producers

Producers convert light energy from the sun into chemical energy stored in their tissues

Second trophic level

Primary consumers

Primary consumers eat producers, transferring energy into their tissues

Third trophic level

Secondary consumers

Secondary consumers eat primary consumers, transferring energy into their tissues

Fourth trophic level

Tertiary consumers

Tertiary consumers eat secondary consumers, transferring energy into their tissues

  • At any trophic level organisms produce waste, or may die; the energy in waste or dead matter is then transferred to decomposers

A food web showing a range of organisms and their trophic levels within a food web. Some organisms occupy more than one level.

Consumers can occupy more than one trophic level in a food web, as they may rely on multiple food sources

You've read 0 of your 5 free revision notes this week

Sign up now. It’s free!

Join the 100,000+ Students that ❤️ Save My Exams

the (exam) results speak for themselves:

Did this page help you?

Lára Marie McIvor

Author: Lára Marie McIvor

Expertise: Biology Lead

Lára graduated from Oxford University in Biological Sciences and has now been a science tutor working in the UK for several years. Lára has a particular interest in the area of infectious disease and epidemiology, and enjoys creating original educational materials that develop confidence and facilitate learning.