ENDOCRINE SYSTEM
ENDOCRINE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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only its target cells get exposed to aldosterone.
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only its target cells contain aldosterone receptors.
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it is able to enter nontarget cells.
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nontarget cells destroy aldosterone before it can produce any effect.
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Detailed explanation-1: -Aldosterone is a steroid hormone (mineralocorticoid ) that regulates salt-water balance in the body. Steroid hormones are lipophilic. They cross the cell membrane but can function only when they bind to specific receptors that are present only in the target cell.
Detailed explanation-2: -Recent studies suggest that steroid hormones use receptors on cellular membranes both to gain access to the intracellular compartment and to modulate cellular functions. These interactions with cell-surface receptors have important physiological consequences.
Detailed explanation-3: -Intracellular hormone receptors are located inside the cell. Hormones that bind to this type of receptor must be able to cross the cell membrane. Steroid hormones are derived from cholesterol and therefore can readily diffuse through the lipid bilayer of the cell membrane to reach the intracellular receptor ([link]).
Detailed explanation-4: -Steroid hormones typically react with receptor sites inside a cell. Because this method of action actually involves synthesis of proteins, it is relatively slow.