Food Chains and Food Webs

Producers, Consumers, and Decomposers#

Every living thing in an ecosystem has a role in the flow of energy. These roles are organized into three main categories: producers, consumers, and decomposers.

Producers#

Producers are organisms that make their own food using energy from the sun through a process called photosynthesis. All producers are plants, algä, or certain bacteria.

Photosynthesis: Using sunlight + water + carbon dioxide → glucose (sugar) + oxygen

Examples: Grass, trees, shrubs, algä, seaweed

Producers are the foundation of every food chain because they capture the sun's energy and convert it into a form that other organisms can use.

Consumers#

Consumers are organisms that cannot make their own food — they must eat (consume) other organisms to get energy.

Herbivores — eat only plants (primary consumers)

• Examples: rabbits, deer, caterpillars, cattle

Carnivores — eat only animals (secondary or tertiary consumers)

• Examples: wolves, eagles, sharks, frogs

Omnivores — eat both plants and animals

• Examples: bears, raccoons, humans, crows

Primary, Secondary, and Tertiary Consumers#

• Primary consumers eat producers directly (herbivores)
• Secondary consumers eat primary consumers
• Tertiary consumers eat secondary consumers (often apex predators)

Decomposers#

Decomposers break down dead organisms and waste materials into simpler substances. They recycle nutrients back into the soil, which producers can then use.

Examples: Fungi (mushrooms), bacteria, earthworms, beetles

Without decomposers, dead material would pile up and nutrients would never be returned to the ecosystem. Decomposers are nature's recyclers.