Concept explainers
To review:
The epinephrine-stimulated activation of glycogen breakdown and identifying primary signal, receptor, transducer, and response.
Introduction:
There is a requirement of precise regulation of anabolic and catabolic reactions, which utilizes proteins, lipids, and carbohydrates. In multicellular organisms, the regulation of such reactions is complex and is maintained by a constant flow of information. The simplest form of transfer of information includes a primary signal, target, and transducer.
Explanation of Solution
The primary signal in any information flow is the molecule thatis responsible for the initiation of information flow, for example, hormones. In the case of glycogen
The transducer is any molecule thatconverts the signal to a cellular response. In this case, the transducer is adenylate cyclase as binding of epinephrine to its receptor activates adenylate cyclase thatconverts ATP (adenosine triphosphate) to cAMP (cyclic adenosine monophosphate), which carries out signal cascade reactions. The response is the final product of the signaling pathway. In epinephrine-stimulated activation of glycogen, breakdown response is the formation of glucose-1-phosphate.
Thus, it can be concluded that the primary signal is epinephrine, the receptor is the epinephrine receptor, the transducer is adenylate cyclase, and the response is glucose-1-phosphate.
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Chapter 16 Solutions
Biochemistry: The Molecular Basis of Life
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