What happens to a blood vessel's diameter when the smooth muscle contracts?

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Multiple Choice

What happens to a blood vessel's diameter when the smooth muscle contracts?

When smooth muscle in the vessel wall contracts, it pulls the walls inward and narrows the lumen, which is exactly vasoconstriction. This reduces the diameter of the vessel and increases resistance to blood flow, helping regulate blood pressure and distribution. If the muscle relaxed, the vessel would widen (vasodilation). No change would imply the smooth muscle isn’t contracting at all, and turbulence refers to chaotic flow patterns rather than a change in the vessel’s diameter.

When smooth muscle in the vessel wall contracts, it pulls the walls inward and narrows the lumen, which is exactly vasoconstriction. This reduces the diameter of the vessel and increases resistance to blood flow, helping regulate blood pressure and distribution. If the muscle relaxed, the vessel would widen (vasodilation). No change would imply the smooth muscle isn’t contracting at all, and turbulence refers to chaotic flow patterns rather than a change in the vessel’s diameter.

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