How Does Energy Flow Through a Food Chain?

Energy flows through a food chain in a linear manner, starting from the sun and moving through various organisms. Here’s a step-by-step explanation:

1. Sunlight: The sun is the primary source of energy for most ecosystems. Plants, algae, and some bacteria capture this energy through photosynthesis.
2. Producers: These are the organisms that convert sunlight into chemical energy (glucose) through photosynthesis. Examples include plants, algae, and phytoplankton.
3. Primary Consumers: These are herbivores that eat the producers. They obtain energy by consuming plants. Examples include deer, rabbits, and zooplankton.
4. Secondary Consumers: These are carnivores that eat the primary consumers. They get their energy by consuming herbivores. Examples include frogs, small fish, and birds.
5. Tertiary Consumers: These are top predators that eat secondary consumers. They obtain energy by consuming other carnivores. Examples include lions, hawks, and sharks.
6. Decomposers: When organisms die, decomposers like bacteria and fungi break down their bodies, returning nutrients to the soil and releasing energy back into the ecosystem.

At each step, some energy is lost as heat, which is why the amount of energy decreases as it moves up the food chain. This is known as the 10% rule, where only about 10% of the energy is transferred from one trophic level to the next.