Explain the structure of nephron.

Explanation

Each kidney has nearly one million complex tubular structures called nephron. Each nephron consists of a filtering corpuscle called renal corpuscle (malpighian body) and a renal tubule. The renal tubule opens into a longer tubule called the collecting duct. The renal tubule begins with a double walled cup shaped structure called the Bowman.s capsule, which encloses a ball of capillaries that delivers fluid to the tubules, called the glomerulus. The bowman.s capsule and the glomerulus together constitute the renal corpuscle. The endothelium of glomerulus has many pores (fenestrae). The external parietal layer of the Bowman.s capsule is made up of simple squamous epithelium and the visceral layer is made of epithelial cells called podocytes. The podocytes end in foot processes which cling to the basement membrane of the glomerulus. The openings between the foot processes are called filtration slits.

The renal tubule continues further to form the proximal convoluted tubule (PCT) followed by a U-shaped loop of Henle (Henle.s loop) that has a thin descending and a thick ascending limb. The ascending limo continues as a highly coiled tubular region called the distal convoluted tubule (DCT). The DCT of many nephrons open into straight tube called collecting duct. The collecting duct runs through the medullary pyramids in the region of the pelvis. Several collecting ducts fuse to form papillary au that delivers urine into the calyces, which opens into the renal pelvis.