The kidneys are a pair of bean-shaped organs. They are positioned below the diaphragm to the left and right side of the spine. The primary blood vessels, the artery and the vein, enter the kidneys at the renal pelvis.
Urine produced in the kidneys flows to the bladder through the ureters. The kidney's structure comprises the renal cortex, renal medulla, and the renal pelvis. Over a million tiny functional entities, called nephrons, can be found in the renal cortex and medulla. They are responsible for the kidneys'diverse functions.
A single nephron consists of the renal corpuscle and an attached tubule. The corpuscle itself is made up of a ball of delicate blood vessels, the glomerulus, which is encased inside a capsule. The capsule serves as a temporary reservoir for primary urine.
180 litres of primary urine are emitted by the capillary blood vessels of the glomeruli every day. Bigger blood components, such as red blood cells and large protein molecules, are retained during this filtration. Thus, primary urine contains all low molecular components of the blood plasma. those that have to be excreted and those that are essential for the body sugars, amino acids and salts.
These components must be returned to the bloodstream. This happens in the nephron's tubuli. There large quantities of water and essential solutes are reabsorbed.
Only about 1.5 liters of the primary urine are excreted as urine every day. The excreted urine contains substances that are unnecessary or can become poisonous to the body if retained in large amounts. This is why the kidneys are also called the body's sewage treatment plant.
Every day, every drop of our blood, about 7 litres, flows through the kidneys over 200 times. The kidneys also perform numerous other tasks in the body. They control the balance of fluids and the level of salts.
and they also play an important role in sustaining the body's acid-base equilibrium. Additionally, the kidneys produce vitamin D and other vital hormones, such as the blood pressure hormone renin or the hormone erythropoietin, which is responsible for the generation of red blood cells.