Capillaries

Definition

Capillaries are the smallest blood vessels in the cardiovascular system, connecting arterioles to venules. They facilitate the exchange of oxygen, nutrients, and waste products between blood and tissues.

5 Must Know Facts For Your Next Test

1. Capillaries have thin walls composed of a single layer of endothelial cells to allow efficient nutrient and gas exchange.
2. They play a critical role in regulating blood flow and pressure within tissues.
3. Capillary density can be affected by factors such as physical activity, nutrition, and overall cardiovascular health.
4. Dysfunction or damage to capillaries can lead to inadequate tissue perfusion and contribute to conditions like edema and hypertension.
5. Nutritional factors such as antioxidants, omega-3 fatty acids, and vitamins C and E support capillary health by reducing oxidative stress.

Review Questions

• What is the primary function of capillaries in the cardiovascular system?
• How do nutritional factors influence capillary health?
• What are the potential consequences of damaged or dysfunctional capillaries?

Related terms

Arterioles: Small branches of arteries that lead into capillaries.

Venules: Small vessels that collect blood from capillaries and transport it to larger veins.

Endothelial Cells: The cells lining the interior surface of blood vessels, including capillaries.