試題詳解

12. Lipid-soluble signaling molecules, such as aldosterone, can diffuse across the cell membranes but affect only target cells because?
(A) Only target cells have responsive DNA segments
(B) Intracellular receptors are present only in target cells
(C) Only target cells have enzymnes that convert aldosterone to active form
(D) Aldosterone-responsive genes are only present in the target cells