THE CELL
CELL COMMUNICATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Epinephrine binds to a cell-surface receptor; the activated receptor stimulates production of the second messenger, cAMP
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Epinephrine binds to a cell-surface receptor; the activated receptor catalyzes the conversion of glycogen to glucose
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Epinephrine diffuses through the plasma membrane; the hormone dimerizes in the cytosol
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Epinephrine is taken into the cell by endocytosis; glycogen is converted to glucose in the endocytotic vesicle
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Detailed explanation-1: -Epinephrine and Norepinephrine Like the glucagon receptor, -adrenergic receptors are linked to a Gs signaling pathway that increases intracellular cAMP. Epinephrine also promotes glycogenolysis and gluconeogenesis through the 1 adrenergic receptor, which is coupled to the Gq/IP3/DAG signaling pathway.
Detailed explanation-2: -In the liver, epinephrine stimulates the breakdown of glycogen to glucose, resulting in an increase in glucose levels in the blood. It also acts to increase the level of circulating free fatty acids.
Detailed explanation-3: -Epinephrine is a protein hormone found in many animals. Epinephrine stimulates a signaling pathway that results in the breakdown of glycogen to glucose in the liver cells.
Detailed explanation-4: -Epinephrine triggers the breakdown of glycogen in liver cells by binding to beta-adrenergic receptors in the plasma membrane of the liver cells. Binding of epinephrine dissociates a G protein subunit from the receptor, which when activated by GTP binds to Adenyl cyclase, another transmembrane protein.