Key Concepts: Food Chains, Webs, and Trophic Levels

Food Chains and Webs

• Food Chain: A single pathway of energy flow
• Food Web: Interconnected food chains in an ecosystem

Trophic Levels

• Level 1: Producers (plants, algae)
• Level 2: Primary consumers (herbivores)
• Level 3: Secondary consumers (carnivores that eat herbivores)
• Level 4: Tertiary consumers (top predators)

Decomposers work at all levels, breaking down dead matter and recycling nutrients.