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Cellular Respiration


Determining if a physical or chemical process is thermodynamically favored depends on the enthalpy and entropy of a system, which in turn leads to estimation or calculation of free energy.

In cellular respiration, carbohydrates are broken down into carbon dioxide and water while producing a net of 34 ATP. ATP is used to measure the energy of a biological system.

Which of the following statements MOST accurately supports cellular respiration?


Cellular respiration is very exothermic but has a decrease in entropy, making the system only slightly thermodynamically favored.


The entropy of the system increases due to a greater number of molecules formed during the reaction, making entropy the only factor that favors the process.


The large value of ATP shows a large amount of energy is required to drive the system forward, which is readily available in cells, making the process thermodynamically favored.


Cellular respiration is driven by both an increase in entropy and a large decrease in enthalpy, resulting in a thermodynamically favored system.