https://www.khanacademy.org/science/ap-biology/ecology-ap/energy-flow-through-ecosystems/v/flow-of-energy-and-matter-through-ecosystems 2024-05-08T17:59:40.799210289Z Flow of energy and matter through ecosystems Energy flows and matter recycles in ecosystems, with the Sun as the primary energy source. Plants, as primary producers, convert sunlight into energy-storing biomolecules. Consumers, like animals, obtain energy by eating plants or other animals. Decomposers break down dead organisms, recycling matter and nutrients. Energy is conserved but often released as heat, while matter constantly cycles through the ecosystem. Sal Khan video https://cdn.kastatic.org/googleusercontent/wi_ooqQppefn_o67MB2y0Pgax1p5vKDVr9mj7_kuG6IK5tFwTUetpM1OigZ75_XEnzZhusHhr41EC3CBqHcgm3LPlA Flow of energy and matter through ecosystems Energy flows and matter recycles in ecosystems, with the Sun as the primary energy source. Plants, as primary producers, convert sunlight into energy-storing biomolecules. Consumers, like animals, obtain energy by eating plants or other animals. Decomposers break down dead organisms, recycling matter and nutrients. Energy is conserved but often released as heat, while matter constantly cycles through the ecosystem. https://cdn.kastatic.org/ka-youtube-converted/TitrRpMUt0I.mp4/TitrRpMUt0I.mp4 626 Energy flow https://www.khanacademy.org/science/ms-biology/x0c5bb03129646fd6:matter-and-energy-in-ecosystems/x0c5bb03129646fd6:matter-and-energy-in-foodwebs/v/worked-example-analyzing-a-generic-food-web 2026-04-15T10:20:35.936477099Z Worked example: Analyzing a generic food web We can analyze the arrows in a food web to identify producers, primary consumers, secondary consumers, and decomposers. Khan Academy video https://cdn.kastatic.org/ka_thumbnails_cache/4cf6477e-517f-47db-af3e-a2a4863f0445_1280_720_base.png Worked example: Analyzing a generic food web We can analyze the arrows in a food web to identify producers, primary consumers, secondary consumers, and decomposers. https://cdn.kastatic.org/ka-youtube-converted/vniXioPlsLA.mp4/vniXioPlsLA.mp4 244 Energy flow https://www.khanacademy.org/science/ap-biology/cellular-energetics/photosynthesis/a/intro-to-photosynthesis 2021-04-29T07:54:51Z Intro to photosynthesis Conversion of light energy to chemical energy. Reactions of photosynthesis, where they take place, and their ecological importance. article https://www.khanacademy.org/science/ap-biology/ecology-ap/energy-flow-through-ecosystems/v/impact-of-changes-to-trophic-pyramids 2023-06-22T09:47:49.118446933Z Impact of changes to trophic pyramids The trophic pyramid illustrates energy transfer within ecosystems, highlighting primary producers, consumers, and decomposers. Energy from the sun is stored as biomass, with only 10% transferred between trophic levels. Ecosystem changes, such as reduced sunlight or pesticide use, can impact the entire pyramid, emphasizing the interconnectedness of ecosystems and the importance of energy cycling. video https://cdn.kastatic.org/googleusercontent/QNOnzKHWj3IrO0I5VNGFmUh2T1RSlfAaKiutE7lMm-p2wLIihlbMNdrYOLoiNWI_JfJpm3iUsgEcjZ-f2fvvDNIrEQ Impact of changes to trophic pyramids The trophic pyramid illustrates energy transfer within ecosystems, highlighting primary producers, consumers, and decomposers. Energy from the sun is stored as biomass, with only 10% transferred between trophic levels. Ecosystem changes, such as reduced sunlight or pesticide use, can impact the entire pyramid, emphasizing the interconnectedness of ecosystems and the importance of energy cycling. https://cdn.kastatic.org/ka-youtube-converted/sV-KQ91Fnck.mp4/sV-KQ91Fnck.mp4 432 Energy flow https://www.khanacademy.org/science/hs-bio/x230b3ff252126bb6:energy-and-matter-in-biological-systems/x230b3ff252126bb6:flow-of-matter-and-energy-through-ecosystems/a/matter-and-energy-in-ecosystems 2024-12-04T19:10:32.241162139Z Trophic levels and energy loss Learn about gross and net primary production, trophic efficiency, and how to model energy loss through ecological pyramids. article https://www.khanacademy.org/science/biology/ecology/intro-to-ecosystems/a/energy-flow-primary-productivity 2023-09-11T02:35:32.836241933Z Energy flow & primary productivity Learn about primary productivity, the (in)efficiency of energy transfer between trophic levels, and how to read ecological pyramids. article https://www.khanacademy.org/science/ms-biology/x0c5bb03129646fd6:matter-and-energy-in-ecosystems/x0c5bb03129646fd6:matter-and-energy-in-foodwebs/e/understand-matter-and-energy-in-food-webs 2026-04-22T04:30:43.362363602Z Understand: Matter and energy in food webs Check your understanding of matter and energy in food webs in this set of free practice questions. Khan Academy exercise https://www.khanacademy.org/science/hs-bio/x230b3ff252126bb6:energy-and-matter-in-biological-systems/x230b3ff252126bb6:flow-of-matter-and-energy-through-ecosystems/a/producers-and-consumers 2024-06-12T19:16:42.550703216Z Food chains and food webs Learn about the roles of organisms as producers and consumers and how they relate to one another in food chains and food webs. article https://www.khanacademy.org/science/hs-bio/x230b3ff252126bb6:energy-and-matter-in-biological-systems/x230b3ff252126bb6:flow-of-matter-and-energy-through-ecosystems/e/understand-matter-and-energy-in-ecosystems 2026-04-08T01:15:04.085520103Z Understand: energy and matter in ecosystems Check your understanding about the flow of energy and matter in ecosystems in this set of free, standards-aligned practice questions. Wieteke Holthuijzen exercise https://www.khanacademy.org/science/ms-biology/x0c5bb03129646fd6:matter-and-energy-in-ecosystems/x0c5bb03129646fd6:matter-and-energy-in-foodwebs/e/apply-matter-and-energy-in-food-webs 2026-04-20T05:52:07.909428702Z Apply: Matter and energy in food webs Apply your understanding of matter and energy in food webs in this set of free practice questions. Khan Academy exercise https://www.khanacademy.org/science/biology/ecology/intro-to-ecosystems/a/what-is-an-ecosystem 2025-06-30T13:17:39.587845569Z What is an ecosystem? Learn what an ecosystem is, how energy and matter move through ecosystems, and what makes an ecosystem stable. article