[Campbell Biology P.1062] According to Figure 45.20 and the accompanying text, which statemen... | Practice Question
According to Figure 45.20 and the accompanying text, which statement accurately describes how epinephrine elicits varied responses in different target cells?
A: Liver cells and smooth muscle cells supplying skeletal muscle respond differently to epinephrine primarily because they express different types of receptors.
B: The smooth muscle cells of blood vessels supplying skeletal muscle and those supplying intestines both use beta-receptors, but activate different intracellular pathways.
C: Epinephrine's effect on liver cells and smooth muscle cells supplying skeletal muscle demonstrates that the same receptor can trigger distinct outcomes due to differences in intracellular signaling.
D: Vasoconstriction in intestinal blood vessels and vasodilation in skeletal muscle blood vessels are both mediated by the same alpha-type receptor.
Explanation
Option C correctly states that epinephrine's effect on liver cells and smooth muscle cells supplying skeletal muscle demonstrates that the same beta-receptor can lead to different outcomes due to variations in intracellular signaling pathways. This is explicitly indicated in Figure 45.20 by the label 'Same receptors but different intracellular proteins not shown ' comparing a and b .