The fluid in glomerular capsule is similar to plasma except that it does not contain a significant amount of plasma protein. The glomerulus differs from other capillaries in the body in that it is drained by an efferent arteriole. Glomerulus and the Bowman's capsule constitute a renal corpuscle, the basic filtration unit of the kidney. The glomerular filtration rate is the rate at which blood is filtered through the glomeruli, and thus measures the renal overall renal function.
