Final answer:
Trophic levels represent the different feeding stages in a food chain or web, including producers, primary consumers, secondary consumers, and tertiary consumers. Energy and biomass decrease from lower to higher trophic levels.
Step-by-step explanation:
The feeding positions in a food chain or web are called trophic levels. Each trophic level represents a different feeding stage and can include producers, primary consumers, secondary consumers, and tertiary consumers. Generally, there are no more than four trophic levels in a food chain because energy and biomass decrease as you move up the levels.