fermentation to continue. While glycolysis and the citric acid cycle produce a few molecules of ATP, the electron transport chain can produce over 30 ATP molecules. This is the main source of ATP for cellular respiration.The electron transport chain is contained within the inner membrane of the mitochondria. In additionto the four protein complexes (identified by areas I, II, III and IV), the location of electron carriers NAD+, NADH, FAD, and FADH2are also indicated. Protein complex I accepts electrons from NADH and complex II accepts electrons from succinate. Complex IV is responsible for transferring the electrons to the final electron acceptor, oxygen. Selecting the button labeled NADHwill show the flow of electrons from NADH to complex IV. The button labeled FADH2will show the path of electrons from succinate to FADH2in complex II(succinate dehydrogenase), followed by movement of these electrons to complex IV.A helpful analogy for understanding how the electron transport chain works is a hydroelectric dam. In a hydroelectric dam, the dam separates an area of high water concentration from an area of low water concentration. Water is allowed to flow downhill through turbines in the dam. As the water flows through these turbines it turns a water wheel. The motion of the wheel is used to generate electricity. In the electron transport chain, the protonsflow downtheir concentration gradient through a proteincalled “ATP synthase”. This protein works like a water wheel and transforms the energy from the movement of the protons into the chemical energyof ATP.did I get thisProcess of Cellular Respirationlearn by doingCombustion vs. Respiration
Energy is released in small portions, so that some of the released energy can be captured in chemical bonds, ultimately as ATP. The process can be regulated at different steps, allowing cells more control over the process.Combustion vs. RespirationBoth combustion and respiration release the same amount of energy. However, because combustion happens all at once, much of that energy is released as heat and light and cannot be captured by the cells. The stepwise process of respiration releases energy slowly so cells can capture the energy in ATP.did I get thisUse of Dietary Nutrients and Stored Fats in Cellular RespirationCellular respiration is a complex, multistep process. Dozens of different enzymes and intermediates are involved. Initial steps are accomplished in the cytoplasm, and additional steps occur in the mitochondria. At various points along the way, intermediates may be removed and used to synthesize fats and other molecules. Similarly, different types of food molecules may “feed in” to cell respiration at specific junctions in the process.
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