#Functional unit of the kidney series#

#Functional unit of the kidney series#

Collectively, the kidney is nothing more than a series of tubes.įor protection and stability, the tubes are encased in a connective tissue matrix. Each nephron has one renal corpuscle, thus, there are approximately 1.2 million renal corpuscles per kidney. Bowman's capsule and the glomerulus form the renal corpuscle which is the initial site of urine formation.

Bowman's capsule surrounds a special capillary network known as the glomerulus. Passing through the proximal convoluted tubule we finally reach the end of our trip at a structure called Bowman's capsule. Our path will take us first through the ascending limb, around the 180 degree turn at the bottom, and then up through the descending limb, eventually leading to the proximal convoluted tubule (another twisting, bending tube). The loop has an ascending limb and a descending limb. Continuing through the collecting duct, we eventually come to another tube called the distal convoluted tubule, a twisting, bending tube (hence the name convoluted) that will take us to a hairpin-shaped tube called the loop of Henle. The first tube that we entered was the collecting duct and serves as a common emptying site for many nephrons. Each kidney contains approximately 1.2 million nephrons, which are a series of hollow tubes composed of a single cell layer, either simple squamous or simple cuboidal.