Which vessel carries blood away from the glomerulus?

• A. Efferent arteriole
• B. Afferent arteriole
• C. Glomerulus
• D. Renal vein

Answer: (A)

In the kidney, blood reaches the glomerulus through the input vessel and is filtered there; the vessel that carries blood away from the glomerulus is the efferent arteriole. Its smaller diameter than the incoming arteriole helps maintain high pressure in the glomerular capillaries, which promotes filtration. After exiting the glomerulus, the blood moves into the peritubular capillaries or vasa recta for reabsorption and secretion along the nephron. The renal vein, by contrast, drains blood from the kidney after filtration, not directly from the glomerulus, and the afferent arteriole brings blood into the glomerulus.