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