The part of nephrons in which the blood plasma is filtered is the glomerulus which is also called Malpighian body. It is a network of capillaries. These capillaries are an extension of the renal artery. The blood plasma is forced into this capillary network under high pressure for filtration. The rate at which blood is filtered in the glomeruli is termed as glomerular filtration rate or the GFR which is an important parameter to examine the functioning of kidneys.
The glomerular network is enclosed in a sac-like structure known as Bowman’s capsule. The Bowman’s capsule is made up of specialised cells called the podocytes. The plasma after passing through the glomerulus enters the podocytes where water and dissolved substances such as sodium and glucose, pass through and travel further in the nephrons. The larger molecules and the blood cells are filtered out in the Bowman’s capsule and only the smaller particles pass through.