#resistance vessels
- Arteriole — A microscopic blood vessel, with a diameter under 100 micrometers, structurally located between the terminal ends of large arteries and the capillary network. Due to the well-developed smooth muscle layer within their walls, arterioles act as the primary resistance vessels of the circulatory system, playing a fundamental role in regulating blood pressure and regional blood flow distribution through vasoconstriction and vasodilation.