THE CELL
CELL COMMUNICATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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intracellular receptors are present only in target cells.
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only target cells retain the appropriate DNA segments.
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only target cells possess the cytosolic enzymes that transduce the testosterone.
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most cells lack the Y chromosome required.
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Detailed explanation-1: -Answer and Explanation: Lipid soluble molecules such as testosterone are only able to affect target cells because, only the target cells will have the necessary intracellular receptors that are able to act on testosterone.
Detailed explanation-2: -Testosterone and estrogen are lipid-soluble signal molecules that cross the plasma membrane by simple diffusion.
Detailed explanation-3: -Why does testosterone, a lipid-soluble / hydrophobic signaling molecule, not affect all cells in the body but only specific cells? a) Only target cells have the cell surface receptor able to bind with testosterone.
Detailed explanation-4: -Hormones mediate changes in target cells by binding to specific hormone receptors. In this way, even though hormones circulate throughout the body and come into contact with many different cell types, they only affect cells that possess the necessary receptors.
Detailed explanation-5: -Lipid soluble cell signaling molecules such as steroid hormones can easily cross the cell membrane owing to their nonpolar nature which makes it energetically favorable for them to interact with the fatty tails of phospholipids. These fatty tails make the middle part of the phospholipid bilayer nonpolar.