What physiological function does vasodilation primarily affect?

Vasodilation primarily affects blood flow by increasing the diameter of blood vessels, particularly the arterioles. When the smooth muscles in the vessel walls relax, it allows for a greater volume of blood to flow through those vessels. This process is important for regulating various physiological demands in the body, such as increased blood flow to active muscles during exercise or delivering nutrients and oxygen to tissues.

The increase in blood flow due to vasodilation can also indirectly influence blood pressure; however, the immediate physiological effect is on the flow of blood itself. As the vessels dilate, blood encounters less resistance, which helps maintain or increase flow rates to specific areas of the body without necessarily changing the overall blood pressure significantly at that moment.