ATP synthesis in mitochondria

Respiration is the process by which organisms combine oxygen with foodstuff molecules, diverting the chemical energy in these substances into life-sustaining processes and discarding, as waste products, carbon dioxide and water. One objective of the degradation of foodstuffs is to conserve the energy in them as the energy-rich compound adenosine triphosphate (ATP). In animal cells the enzymes that catalyze the individual steps involved in respiration and energy conservation are located in highly organized rod-shaped compartments of the cell called mitochondria.

The mechanism of ATP synthesis appears to be as follows. During the transfer of electrons from respiratory substrates to oxygen, protons are pumped across the inner mitochondrial membrane from the inside to the outside. Thus, respiration generates an electrochemical gradient across the membrane. Attached to the inner mitochondrial membrane is a complex enzyme (ATP synthase). This enzyme complex makes ATP utilizing the electrochemical gradient created by the electron transfer. The precise mechanism by which the ATP synthase complex converts the energy stored in the electrochemical gradient to the chemical bond nergy in ATP is not well understood. The question I have been asking: "How is ATP made?"

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