2.8: Metabolic Controls of Energy
- Page ID
- 1726
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It is also noteworthy that cells do not usually have both catabolic and anabolic processes for the same molecules (for example, breakdown of glucose and synthesis of glucose, shown on the previous page) occurring simultaneously inside of them because the cell would see no net production of anything but heat and a loss of ATPs with each turn of the cycle. Such cycles are called futile cycles and cells have controls in place to limit the extent to which they occur. Since futile cycles can, in fact, yield heat, they are sources of heat in some types of tissue.
Dr. Kevin Ahern and Dr. Indira Rajagopal (Oregon State University)