Copyright Pearson Prentice Hall 3–2 Energy Flow Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Producers Photosynthesis is responsible for adding oxygen to—and removing carbon dioxide from—Earth's atmosphere. Sunlight is the main energy source for life on Earth. Some types of organisms rely on the energy stored in inorganic chemical compounds. Plants use the energy from sunlight to carry out the process of photosynthesis. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Consumers There are many different types of heterotrophs. Herbivores eat plants. Carnivores eat animals. Omnivores eat both plants and animals. Detritivores feed on plant and animal remains and other dead matter. Decomposers, like bacteria and fungi, break down organic matter. Copyright Pearson Prentice Hall

Feeding Relationships How does energy flow through living systems? Copyright Pearson Prentice Hall

Feeding Relationships Energy flows through an ecosystem in one direction, from the sun or inorganic compounds to autotrophs (producers) and then to various heterotrophs (consumers). **From light energy to chemical energy **Making sugars(stored chemical energy) Copyright Pearson Prentice Hall

Feeding Relationships In some marine food chains, the producers are microscopic algae and the top carnivore is four steps removed from the producer. Think: arrows represent energy…what’s happing to the amount? What’s happening to size of organism? Small Fish Zooplankton Squid Food chains show the one-way flow of energy in an ecosystem. In this marine food chain, energy is passed from the producers (algae) to four different groups of consumers. Shark Algae Copyright Pearson Prentice Hall

Feeding Relationships This food web shows some of the feeding relationships in a salt-marsh community. How many food chains can you identify in the food web? This illustration of a food web shows some of the feeding relationships in a salt marsh. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Ecological Pyramids How efficient is the transfer of energy among organisms in an ecosystem? Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Ecological Pyramids Energy Pyramid: Shows the relative amount of energy available at each trophic level. Only part of the energy that is stored in one trophic level is passed on to the next level. The rest is lost as heat, undigested, or used to run you on a daily basis. 0.1% Third-level consumers 1% Second-level consumers 10% First-level consumers Ecological pyramids show the decreasing amounts of energy, living tissue, or number of organisms at successive feeding levels. The pyramid is divided into sections that represent each trophic level. Because each trophic level harvests only about one tenth of the energy from the level below, it can support only about one tenth the amount of living tissue. 100% Producers Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Ecological Pyramids The more levels that exist between a producer and a top-level consumer in an ecosystem, the less energy that remains from the original amount. Only about 10 percent of the energy available within one trophic level is transferred to organisms at the next trophic level. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Ecological Pyramids Biomass Pyramid: Represents the amount of living organic matter at each trophic level. Typically, the greatest biomass is at the base of the pyramid. What do you notice about the amounts of mass as you go up/down the pyramid? 50 grams of human tissue 500 grams of chicken 5000 grams of grain Ecological pyramids show the decreasing amounts of energy, living tissue, or number of organisms at successive feeding levels. The pyramid is divided into sections that represent each trophic level. Because each trophic level harvests only about one tenth of the energy from the level below, it can support only about one tenth the amount of living tissue. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall Ecological Pyramids Pyramid of Numbers: Shows the relative number of individual organisms at each trophic level. Ecological pyramids show the decreasing amounts of energy, living tissue, or number of organisms at successive feeding levels. The pyramid is divided into sections that represent each trophic level. Because each trophic level harvests only about one tenth of the energy from the level below, it can support only about one tenth the amount of living tissue. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 3–2 Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 3–2 The main source of energy for life on Earth is organic chemical compounds. inorganic chemical compounds. sunlight. producers. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 3–2 Organisms that feed on plant and animal remains and other dead matter are detritivores. carnivores. herbivores. autotrophs. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 3–2 How does a food web differ from a food chain? A food web contains a single series of energy transfers. A food web links many food chains together. A food web has only one trophic level. A food web shows how energy passes from producer to consumer. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 3–2 In a biomass pyramid, the base of the pyramid represents the mass of heterotrophs. primary consumers. producers. top level carnivores. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 3–2 The amount of energy represented in each trophic level of consumers in an energy pyramid is about 10% of the level below it. 90% of the level below it. 10% more than the level below it. 90% more than the level below it. Copyright Pearson Prentice Hall

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