In renal physiology, ultrafiltration occurs at the barrier between the blood and the filtrate in the glomerular capsule (Bowman's capsule) in the kidneys. ... Blood flows into these capillaries through the afferent arterioles and leaves through the efferent arterioles.

How does ultrafiltration occur in the glomerulus?

The process by which glomerular filtration occurs is called renal ultrafiltration. The force of hydrostatic pressure in the glomerulus (the force of pressure exerted from the pressure of the blood vessel itself) is the driving force that pushes filtrate out of the capillaries and into the slits in the nephron.

How does ultrafiltration occur?

Ultrafiltration occurs when fluid passes across a semipermeable membrane (a membrane that allows some substances to pass through but not others) due to a driving pressure.