Normally, the flow of electrons to O2 is tightlylinked to the production of ATP via the electrochemicalgradient. If ATP synthase is inhibited, for example, elec-trons do not flow down the electron-transport chain andrespiration ceases. Since the 1940s, several substances—such as 2,4-dinitrophenol—have been known to uncou-ple electron flow from ATP synthesis. Dinitrophenol wasonce prescribed as a diet drug to aid in weight loss. Howwould an uncoupler of oxidative phosphorylation pro-mote weight loss? Why do you suppose dinitrophenol isno longer prescribed?

Normally, the flow of electrons to O2 is tightlylinked to the production of ATP via the electrochemicalgradient. If ATP synthase is inhibited, for example, elec-trons do not flow down the electron-transport chain andrespiration ceases. Since the 1940s, several substances—such as 2,4-dinitrophenol—have been known to uncou-ple electron flow from ATP synthesis. Dinitrophenol wasonce prescribed as a diet drug to aid in weight loss. Howwould an uncoupler of oxidative phosphorylation pro-mote weight loss? Why do you suppose dinitrophenol isno longer prescribed?

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter2: Cell Physiology

Section: Chapter Questions

Problem 2TAHL

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