Concept explainers
To discuss:
The function of second-messenger systems associated with the plasma membrane; specific roles of membrane receptors, G proteins, adenylate cyclase, cyclic adenosine monophosphate, and kinases in the cAMP second-messenger system.
Introduction:
Cellular membrane, nucleus, and cytoplasm are the three major components of a cell. Cellular membrane, which surrounds the entire cell, is composed of phospholipids and proteins. Peripheral proteins are generally found on the membrane surface and are temporarily attached to one face of the plasma membrane. Membrane proteins that traverse the entire cell membrane alone can serve as a membrane channel. A membrane channel aids in the transfer of solutes from one side of the cell membrane, which is selectively permeable, to the other side of the membrane. Such integral proteins are called as transmembrane proteins.
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Anatomy & Physiology: The Unity of Form and Function
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