THE CELL
CELL COMMUNICATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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operate in animals, but not in plants.
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are absent in bacteria, but are plentiful in yeast.
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involve the release of hormones into the blood.
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often involve the binding of signal molecules to a protein on the surface of a target cell.
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Detailed explanation-1: -Once a hormone binds to the extracellular portion of the cell-surface receptor, the intracellular portion of the receptor changes shape, resulting in activation of a chain of events that is called a signaling pathway or signaling cascade. The events in the cascade occur in a defined series of events.
Detailed explanation-2: -Cells have proteins called receptors that bind to signaling molecules and initiate a physiological response. Different receptors are specific for different molecules. Dopamine receptors bind dopamine, insulin receptors bind insulin, nerve growth factor receptors bind nerve growth factor, and so on.
Detailed explanation-3: -Reception is the stage of the cell signaling in which a chemical signal is “detected” when the signaling molecule binds to a receptor protein located at the cell’s surface. The process going on at the receiving end of a cellular conversation can be divided into three stages: reception, transduction, and response.