Running on Energy
Everything runs on energy!
Goal:
Goal:
Energy is needed to light and heat your home, run your transportation, and cook your food. You use energy when you walk to school, and even when you raise your hand to ask your teacher a question!
It takes energy for you to use your eyes and your brain to read this page. In fact, everything you do, whether it's breathing, sleeping, eating, walking, working, or even digesting, takes energy! But where does all that energy come from? Click through the slides to find out.
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The Sun Living things must get their energy from the place they live. But where could that be? Look up--it comes from the sun! All of the energy, all over the world, in all its different forms, begins as energy from the sun.
Plants Make Food When it comes to energy, plants have a very special job. Only plants can take the energy from the sun and turn it into food energy for themselves and other living things. First of all, a plant takes in sunlight and changes it into food for itself. This food is a type of sugar called a carbohydrate. When a plant takes sunlight to make food, the process is called photosynthesis. Photosynthesis changes sunlight and air into sugar. Without photosynthesis, there would be no life on Earth.
Energy From Plants Many animals get their energy from plants. The food energy in plants is passed on to animals when they eat plants. This energy then moves on to other animals when they eat the animals that ate the plants. This is how energy moves through a system. It starts with the sun, moves on to plants, then to animals that eat the plants, then to animals that eat animals, and then to other animals that eat those animals. It's a long chain, starting with the sun.
So, in a way, every time you eat anything, you are eating part of the sun! Think about an apple. The apple tree used sunlight to make food to grow strong and healthy, and fed the developing apples with this energy. What about a hamburger? If you eat a hamburger, you are getting energy from eating a cow, which got its energy from eating grass, which got its energy from the sun. Food Chains The way the energy moves from the sun to other living things is called a food chain. Most food chains start with the sun. There are a few other organisms that can produce energy, but the first link in a food chain is almost always between the sun and plants. Anything that can make its own food is called a producer.
Consumers: Herbivores The next link in the food chain is the animals that eat plants. These animals are called consumers. Grasshoppers, rabbits, and cows are all consumers. There are many other consumers. They all eat plants. You are a consumer, too. You eat salads, vegetables, and plants of many different kinds. Animals that only eat plants are called herbivores.
Consumers: Carnivores and Omnivores Some consumers eat only other consumers. Foxes eat rabbits, snakes and owls eat mice, and most birds eat bugs and worms of one type or another. These creatures are called carnivores. Some consumers eat both producers and consumers. Bears eat fish, roots, and berries. You might eat oranges, beans, carrots, and some type of meat or fish. If so, you are an omnivore.
Scavengers What happens to animals when they die? Scavengers and decomposers eat them. Scavengers are animals that specialize in eating only other animals that have died. Most scavengers do not kill their own food. Vultures, hyenas, and certain kinds of ants, beetles, and worms are scavengers. They are very important because they provide a sort of clean-up service for energy systems.
Decomposers Decomposers are tiny living things--microorganisms--that eat dead plants and animals. Decomposers are the final link in a food chain. This makes them very important, because they break dead things down into soil so that plants can use them to begin another food chain.
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Eating the Sun?
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