Efferent arteriole

Definition

The efferent arteriole is a blood vessel that carries blood away from the glomerulus in the kidney. It plays a crucial role in regulating blood pressure and filtration rate within the nephron.

5 Must Know Facts For Your Next Test

1. The efferent arteriole is smaller in diameter compared to the afferent arteriole, which helps maintain high pressure in the glomerulus.
2. It helps regulate the filtration rate by controlling blood flow out of the glomerulus.
3. The efferent arteriole branches into capillaries known as peritubular capillaries and vasa recta, which supply oxygen and nutrients to kidney tissues.
4. Constriction of the efferent arteriole increases glomerular filtration rate (GFR).
5. The balance between afferent and efferent arteriolar resistance is essential for proper kidney function.

Review Questions

• What is the main role of the efferent arteriole in kidney function?
• How does the diameter of the efferent arteriole compare to that of the afferent arteriole?
• What happens to glomerular filtration rate when the efferent arteriole constricts?

Related terms

Afferent Arteriole: A blood vessel that carries blood to the glomerulus, larger in diameter than the efferent arteriole.

Glomerulus: A network of capillaries within Bowman's capsule where blood filtration begins.

Nephron: The functional unit of the kidney responsible for filtering blood and producing urine.