Arterioles

Definition

Arterioles are small blood vessels that extend and branch out from arteries to capillaries. They play a key role in regulating blood flow and pressure by constricting or dilating.

5 Must Know Facts For Your Next Test

1. Arterioles are primarily responsible for the regulation of blood pressure through vasoconstriction and vasodilation.
2. The walls of arterioles contain smooth muscle, which allows them to change diameter.
3. Arterioles connect the arterial system with the capillary networks, facilitating nutrient and oxygen delivery to tissues.
4. The autonomic nervous system and various hormones influence arteriole function.
5. Diseases such as hypertension can result from dysfunction in arteriole regulation.

Review Questions

• What role do arterioles play in regulating blood pressure?
• How do arterioles differ from arteries and capillaries in terms of structure and function?
• Which part of the nervous system influences the constriction and dilation of arterioles?

Related terms

arteries: large blood vessels that carry oxygenated blood away from the heart to various parts of the body

capillaries: tiny blood vessels where the exchange of water, nutrients, and waste products occurs between blood and tissues

vasoconstriction: the narrowing of blood vessels resulting from contraction of muscular walls, particularly in arterioles