Ambient temperature is the term used to identify the surrounding or environmental temperature. It is the nature and tendency of all things to approach ambient temperature. If you are in a room, then the ambient temperature is the room temperature.
An arteriole is a small-diameter blood vessel in the microcirculation that extends and branches out from an artery and leads to capillaries. Arterioles have muscular walls and are the primary site of vascular resistance. The greatest change in blood pressure and velocity of blood flow occurs at the transition of arterioles to capillaries.
Arterioles are tiny branches of arteries that lead to capillaries. These are also under the control of the sympathetic nervous system, and constrict and dialate, to regulate blood flow. 1  Transport blood from arteries to capillaries.  Arterioles are the main regulators of blood flow and pressure.