Key Points continued

• Receptors bind signals with high specificity and affinity and undergo a conformational change sufficient to initiate a biochemical reaction. Receptor number and activity are subject to regulation.

• Receptors in the G-protein-coupled receptor superfamily are glycoproteins that thread through the plasma membrane seven times and transmit their signal by activating guanine nucleotide-binding proteins.

• The concept of the second messenger is that information from activated surface receptors is transmitted to intracellular effectors by molecules that initiate biochemical responses within the cell and its organelles. The ensuing responses are a function of the differentiated state of the cell rather than of the molecule that causes activation or inhibition of cellular responses.

• Receptors for steroid hormones, thyroid hormone, and vitamins A and D are transcription factors that bind directly to response elements in DNA and, when bound to their agonists, activate or repress expression of responsive genes.

• Secretory cells synthesize their products from simple precursor molecules taken up from the blood.

• For chemical signals to deliver information effectively, they must be eliminated from the vicinity of the receptor as soon as possible after the message has been received. This is accomplished by metabolic degradation, reuptake into secretory granules, or dilution.

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Get Rid of Gallstones Naturally

Get Rid of Gallstones Naturally

One of the main home remedies that you need to follow to prevent gallstones is a healthy lifestyle. You need to maintain a healthy body weight to prevent gallstones. The following are the best home remedies that will help you to treat and prevent gallstones.

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