Food Chains and Food Webs Energy enters most ecosystems as sunlight and is converted into food molecules by producers. This energy is transferred to each organism that eats a producer, and then to other organisms that feed on these consumers. The movement of energy through an ecosystem can be shown in diagrams called food chains and food webs.

Food Chains Every living thing needs energy in order to live. Every time animals do something (run, jump) they use energy to do so. Energy is necessary for living beings to live and grow. Animals get energy from the food they eat, and all living things get energy from food. Plants use sunlight, water and nutrients to get energy (photosynthesis).

Food Chains A food chain shows how each living thing gets food, and how nutrients and energy are passed from creature to creature. Food chains begin with plant-life, and end with animal-life. Some animals eat plants, some animals eat other animals. http://www.sheppardsoftware.com/content/animals/kidscorner/foodchain/decomposers.htm

There is actually even more to this chain. After a hawk dies, fungi (like mushrooms) and other decomposers break down the dead hawk, and turn the remains of the hawk into nutrients, which are released into the soil. The nutrients (plus sun and water) then cause the grass to grow. It's a full circle of life and energy!!

Food Webs A food web consists of the many overlapping food chains in an ecosystem. A food web is more realistic accurate than a food chain.

Which is more stable? A food web is more stable than a food chain.

A Typical Food Web Comprised of several food chains

Energy Pyramids An energy pyramid shows the amount of energy that moves from one feeding level to another in a food web. Where is the most energy available? Why does less energy become available at each level?

How the numbers work in an Energy Pyramid Only 10% of the available energy moves to the next trophic level. ***Most of the energy is lost as heat.