The glomerulus is surrounded by a cup-shaped structure called Bowman’s capsule. The Bowman’s capsule and the glomerulus together are called the Malpighian body. This is lined by a single layer of flat epithelial cells. The inner membrane of the Bowman’s capsule is apposed closely to the walls of glomerular capillaries. Each Bowman’s capsule leads into a renal (kidney) tubule. The renal tubule is made up of a first convoluted tubule, (descending and ascending tubules with a Henle’s loop in between) and a second convoluted tubule leading to a large collecting duct (also called the duct of Belini). The collecting duct passes through the medulla and opens into the pelvis of the kidney at the apex of a pyramid (Fig.19.4). The Malpighian body, proximal and distal convoluted tubules lie in the cortex., while Henle’s loop and main collecting ducts are present in the medulla. The proximal convoluted tubule is lined by ciliated cubical epithelial cells, the ascending limb and the distal convoluted tubule by cuboidal epithelium and the descending limb is lined by the flattened epithelial cells.