Finger temperature is directly and actively regulated by which vessels?

The regulation of finger temperature is primarily influenced by arterioles, which are small branches of arteries that lead to capillaries. Arterioles play a crucial role in controlling blood flow through vasoconstriction and vasodilation, thereby directly impacting the amount of warm blood reaching the skin's surface. This process allows for active regulation of temperature based on the body's needs, such as conserving heat in colder environments or dissipating heat during warmer conditions.

By adjusting the diameter of the arterioles, the body can increase or decrease blood flow to the fingers, affecting their temperature. This dynamic response is essential for thermoregulation and maintaining homeostasis within the body. Other vessels like capillaries, veins, and venules are involved in the overall circulatory system and may contribute to temperature regulation in different ways, but they do not have the same direct and active role as arterioles in modifying blood flow to the fingers specifically.