What is a food chain and how energy flows through it?

What is a food chain and how energy flows through it?

• A. A chain of animals moving in a straight line.
• B. A sequence showing who eats whom; energy flows from producers to consumers and decreases at each step.
• C. A map of habitats.
• D. Energy flows from consumers to producers.

Answer: (B)

A food chain is a simple sequence that shows who eats whom in an ecosystem and how energy moves through it. It starts with producers, usually plants, that capture sunlight and make their own food. Energy then moves to a primary consumer that eats the plants, then to a secondary consumer that eats the primary, and so on. At each step, most energy is used for life processes or lost as heat, so only a portion passes to the next organism. That’s why energy decreases as you move along the chain and why food chains are relatively short. A food chain isn’t about a line of animals moving, a map of habitats, or energy flowing from consumers to producers—the energy flow starts with the sun, goes to producers, and then to consumers.

A food chain is a simple sequence that shows who eats whom in an ecosystem and how energy moves through it. It starts with producers, usually plants, that capture sunlight and make their own food. Energy then moves to a primary consumer that eats the plants, then to a secondary consumer that eats the primary, and so on. At each step, most energy is used for life processes or lost as heat, so only a portion passes to the next organism. That’s why energy decreases as you move along the chain and why food chains are relatively short. A food chain isn’t about a line of animals moving, a map of habitats, or energy flowing from consumers to producers—the energy flow starts with the sun, goes to producers, and then to consumers.