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Energy Pyramid. What is it ?. An energy pyramid shows that each level of a food chain passes on less food energy than the level before it. Where does the energy go?. Most of the energy in each level is used at that level. Only a little energy is passed to the next level !!.
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Energy Pyramid What is it ? An energy pyramid shows that each level of a food chain passes on less food energy than the level before it. Where does the energy go? Most of the energy in each level is used at that level. Only a little energy is passed to the next level !!
Energy Explained Energy is in everything. It (Energy) makes everything happen.We buy energy, sell energy, eat energy, waste energy, talk a little about conserving energy, fight over energy -- and kids use it to chase pigeons. You can't understand animals, biology, physics, chemistry, electronics, volcanoes, or any field of science, engineering, or economics, without understanding how energy behaves.
Energy Pyramid • Energy Pyramids • What is an energy pyramid • An energy pyramid is a graphical model of energy flow in a community. The different levels represent different groups of organisms that might compose a food chain. From the bottom-up, they are as follows: • Producers — bring energy from nonliving sources into the community • Primary consumers — eat the producers, which makes them herbivores in most communities • Secondary consumers — eat the primary consumers, which makes them carnivores • Tertiary consumers — eat the secondary consumers • In some food chains, there is a fourth consumer level, and rarely, a fifth. Have you ever wondered why there are limits to the lengths of food chains?
Because there is less and less energy to go around as it moves through the animal food chain, there are less and less animals; and even though some of the animals get pretty big, the total mass and weight of those animals is much less than the total mass and weight of the Primary Producers. The little Primary Producers in the oceans have to keep busy - not just busy making carbohydrates from sunlight, but also busy reproducing themselves. The typical life span of one of these little phytoplankton critters is just 1 to 5 days. So we need them to stay focussed, stay numerous, and keep busy, busy, busy. All other living things depend on them. It was good to be a big shark on top of the food pyramid, but Bob never forgot his debt to the photoplankton. • THE BOTTOM IS THE TOP The Tiny Little Critters that Weigh More than the Big Guys: As we said in previous pages, energy on land moves from plant to animal to animal in bite sized chunks. For almost all animals, the energy that allows them to "keep on going" comes from the sun. But animals can't get energy directly from the sun (except sometimes for warmth). They need help. In the ocean, that help comes from a whole bunch of little tiny greenish critters (organisms might be the word more sophisticated sources would use) called phytoplankton (or photoplankton?). Phytoplankton do for ocean animals what the green plants on land do for the land animals. They make themselves into food for everyone else. Isn't that thoughtful?
Yup, they are the ones (pretty much the only ones in the ocean) that turn sunlight and carbon and oxygen into glucose and other simple sugars (by a process called photosynthesis) and other molecules that animals can eat. From this tiny but very numerous beginning the sun's energy begins its progression up through the food chain. But as the energy moves up the food chain from phytoplankton to animal to animal there is less and less of it available for animals to use (see the previous section on Energy Flow through Plants and Animals). • Another term that is often used instead of phytoplankton is photoplankton. This is because the bacteria and algae that float in oceans and lakes and do photosynthesis are no longer considered to be plants by most scientists. Phyto means plant. Photo just refers to light and so is more general and can be used to describe any plankton that is able to do photosynthesis. But since people use both words we will use both words too. This will either totally confuse you or make you smarter and less uptight about nomenclature. See Dr. G's beautiful answer about whale and dolphin names to get some fascinating know-it-all information on naming things.
The above drawing is just one example of the countless pyramids that can be drawn. • You might put a sperm whale on top, and some different sizes of squid in between. On land you might put lions, and tigers, and bears (oh my!) on the top, green plants on the bottom, and various insects and herbivores in between. Or you could add some seals above the fish because seals mostly eat fish, and then you could put a polar bear on top of the seals because polar bears mostly eat seals. I'll bet if you thought about it, you could come up with some energy pyramids of your own. But remember that most ecosystems are very complicated and an energy pyramid is just to sort of show the basic idea. There is no way we could really show all the possible ways that animals eat each other and all the possible ways that energy moves through the food chain. The main point is to show that there is less and less energy available as it moves up the food chain. • That's why the pyramid is big on the bottom and small on the top. There is a lot more energy available to animals on the bottom than on the top. • But maybe we shouldn't call the widest part of the pyramid the bottom. Maybe we should call it the "Start". It is the place where energy starts its journey through the food chain.
Humans and Energy Pyramids • Food Energy Pyramids • Flow of energy through a food chain. As energy passes to a higher tropic level, approximately 90% of the useful energy is lost. High tropic levels contain less energy and fewer organisms than lower levels. • At each tropic level in a food chain, energy is used by the organisms at that level to maintain their own life process. Because of the 2nd law of energy, some energy is lost to the surroundings as heat. it is estimated that in going from one tropic level to the next, about 90 % of the energy is lost.In moving to the next tropic level, only 10 % of the original energy is available. By the third tropic level only 1% of the energy is available. • Food Supply - Eat grain rather than Meat • Energy is used much more efficiently if humans eat plants (first tropic level) instead of meat (second tropic level. A given area of farmland can support more people if the crops are fed directly to people rather than to livestock that people then eat. • For example if a man needs 3,000 Calories per day, then 30,000 Cal beef are needed, which in turn need 300,000 Cal of corn, which in turn means 30,000,000 Cal of sunshine. This works out to be 1.5 acres of corn per day per person. If the person ate corn directly then 10 people could be supported by the same 1.5 acres of corn.
Definitions: Autotrophs - Organisms that produce their own food through photosynthesis. Consumers - Organisms that consume other organisms for food. Decomposers - Organisms that break down the remains of plants and animals. Detritus food chain - Transforms litter into nutrients. Energy-flow diagram -The movement of energy from one trophic level to the next. Energy pyramid - The flow of energy from the producer through the various consumers. Food webs - Diagrams illustrating the complex interaction of organisms in an ecosystem. Heterotrophs - Organisms that consume autotrophs or other heterotrophs for food and use their energy. Producers - Organisms that carry on photosynthesis and, thus, create their own food. Pyramid - A diagram illustrating the flow of a commodity through the ecosystem.a) Pyramid of biomass - A pyramid based on chemical energy.b) Pyramid of numbers - A pyramid based on the number of organisms involved at various levels. Trophic level - Each level in an energy pyramid.