urinary system provides the excretion of nitrogenous wastes generated in the process of metabolism and fluid, regulates blood pressure, blood volume, acid-base balance and electrolyte balance.The central authorities of the urinary system are the kidneys.
consider the structure of the kidney.Kidneys are located symmetrically on both sides of the spine at the level of thoracic XII to I-II of the lumbar vertebrae, retroperitoneal, surrounded by a thick layer of fat tissue.Each kidney distinguish front and rear surfaces, the upper and lower poles, lateral and medial side.Through the gate to the kidney enters and leaves the neurovascular bundle.The right kidney is slightly lower than the left, which is associated with the liver located above.The structure of the kidney it allows limited movement in a vertical position.The situation depends on the type of kidney human constitution (hypersthenic, asthenic or normostenicheskaya).Gates kidneys empty into the renal pelvis, large and small cups, where the tops of the pyramids in the form of renal papillae.On the surface of the papilla there are small holes through which urine is released.
internal structure of the kidney rather complicated.Nephron - the basic structural unit of the kidney, providing their work.The number of nephrons in both kidneys reaches 3-4 million.The nephron is composed of vascular glomeruli, renal tubules and capsules.
structure of the kidney and the nephron
are two types of nephrons - superficial or cortical and deep or juxtaglomerular.The juxtaglomerular glomeruli is a long loop of Henle, which ends in the renal papilla.Glomerular capillaries endothelium covered with pores through which the urine ultrafiltration.Glomerular capillaries have a basement membrane.Epithelial cells resemble pads with protuberances which are coated with capillary outside.Scion form a basement membrane, it has a critical role in filtering urine and other renal function.
Vascular renal glomerulus is formed capillaries, which are separated by causing blood vessels, abductor arterioles and secondary capillary network feeding the tubule.The juxtaglomerular apparatus focused special cells that produce renin.This substance has been actively involved in the maintenance of blood pressure levels.Most tubules located in the medulla of the kidneys.Because the discharge vessel has considerably resulting in the glomeruli, a relatively high pressure (about 60 mm Hg) and filtering occurs across the flowing blood.The initial part of the tubule forms a capsule around the glomerulus Shymlanskaya-Bowman.A ball with a capsule called renal or Malpighian corpuscle.
Urinary tubule has a complex structure.Straight sections of tubules, loops of Henle and sbornve urinary tube located in the medulla and winding sections of the tubules are located near the glomeruli and form with them the kidney cortex.
structure of the kidney offers continuous operation.In this part of the glomerular works, and the other - it is at rest.Whole blood which is in the human body, flows through the kidneys within one hour.For Sutoki passes through the kidneys 1500-2000 liters of blood.Components urine mainly fall in renal blood, but some are formed directly in the kidney, for example, ammonia and gipurovaya acid.
We have reviewed the structure of the kidney - the main organ of the urinary system, providing excretion of metabolic products and excess fluid, as well as regulating the internal homeostasis of the human body.
