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Khan Academy
Khan Academy offers free educational resources on various topics, including biology, algebra, geometry, and more.
Khan Academy
Khan Academy
Energy flow & primary productivity (article) | Khan Academy
Learn about primary productivity, the (in)efficiency of energy transfer between trophic levels, and how to read ecological pyramids.
Khan Academy
Review of trophic levels in ecology, including producers, consumers, and decomposers.
Intro to photosynthesis - Khan Academy
2016年7月17日 · They introduce chemical energy and fixed carbon into ecosystems by using light to synthesize sugars. Since these organisms produce their own food—that is, fix their own …
Steps of cellular respiration - Khan Academy
The NADH and FADH 2 made in other steps deposit their electrons in the electron transport chain, turning back into their "empty" forms (NAD + and FAD ). As electrons move down the …
The light-dependent reactions - Khan Academy
In this article, we'll explore the light-dependent reactions as they take place during photosynthesis in plants. We'll trace how light energy is absorbed by pigment molecules, how reaction center …
DNA structure and replication review - Khan Academy
Review the structure and replication of DNA, including key concepts and mechanisms.