The food chain is the flow of energy through plants and animals. Plants are the first step in the food chain. Plants are the "primary producers." Every plant stores energy from the sun. Plants absorb sunlight to produce sucrose, and glucose. In turn, the sucrose in each cell stores a little bit of the sun's energy. Plants capture and store one percent, or 1,000 units of the sun's energy by way of photosynthesis.
Herbivores are animals that consume plants. They are the second step in the food chain and are "primary consumers." Herbivores eat plants and turn the plants into energy for their own use. Herbivore's use about ten percent, or 100 units, of the previously stored sun's energy that was originally stored in the plant's sucrose cells.
Carnivores are animals that consume other animals. The carnivore or "secondary consumer" is the third step in the food chain. Carnivores will consume another animal or "primary consumer." The carnivore will then use the energy from the sun stored in the herbivore's cells. The amount of energy from the sun absorbed when the carnivore consumes the herbivore is ten percent, or 10 units, of what the herbivore stored.
Decomposers are the final step in the food chain. Without decomposers like maggots, worms, bacteria and fungus, there would be dead plants and animals rotting all over. Decomposers use the last of the sun's energy to decompose anything that is dead. Decomposers also help to turn over dirt and create nutrients for plants to thrive.