Peripheral resistance

Definition

Peripheral resistance is the opposition to blood flow provided by the blood vessels outside of the heart and central circulatory system. It primarily occurs in smaller arteries and arterioles, affecting overall blood pressure and flow rates.

5 Must Know Facts For Your Next Test

1. Peripheral resistance is influenced by factors such as vessel diameter, blood viscosity, and total vessel length.
2. An increase in peripheral resistance leads to higher arterial blood pressure.
3. Vasoconstriction increases peripheral resistance while vasodilation decreases it.
4. Hormonal signals like adrenaline can affect peripheral resistance by changing vessel diameter.
5. Peripheral resistance plays a key role in conditions like hypertension (high blood pressure).

Review Questions

• What effect does vasoconstriction have on peripheral resistance?
• How does an increase in peripheral resistance impact arterial blood pressure?
• Name two factors that influence peripheral resistance.

Related terms

Blood Pressure: The force exerted by circulating blood on the walls of the blood vessels.

Arterioles:

Small branches of arteries leading into capillaries, crucial for regulating blood flow and pressure.

Vasoconstriction: The narrowing of blood vessels resulting from contraction of the muscular wall of the vessels, increasing peripheral resistance.