These reduce blood flow are called what?

These reduce blood flow are called what?

• A. Vasoconstrictors
• B. Vasodilators
• C. Vascular factors
• D. Platelets

Answer: (C)

Blood flow is reduced when the diameter of the vessels narrows, so factors that influence vessel tone are the ones that determine how much flow changes. These influences are collectively called vascular factors. A specific example is a vasoconstrictor, which directly narrows arterioles and decreases flow. Vasodilators would do the opposite by widening vessels and increasing flow. Platelets mainly drive clot formation and can affect flow indirectly, but they’re not the general category for reducing flow. So the broad term vascular factors best fits the idea of the elements that decrease blood flow, since it includes vasoconstriction among other influences on vessel diameter.

Blood flow is reduced when the diameter of the vessels narrows, so factors that influence vessel tone are the ones that determine how much flow changes. These influences are collectively called vascular factors. A specific example is a vasoconstrictor, which directly narrows arterioles and decreases flow. Vasodilators would do the opposite by widening vessels and increasing flow. Platelets mainly drive clot formation and can affect flow indirectly, but they’re not the general category for reducing flow. So the broad term vascular factors best fits the idea of the elements that decrease blood flow, since it includes vasoconstriction among other influences on vessel diameter.