Urinary system

Urinary system

• The organ system, specialized in the elimination of metabolic products and foreign substances, ensures the maintenance of an optimal composition of the internal environment of the body (homeostasis) and its normal functioning.
• Includes organs forming (kidneys), accumulating and secreting (ureters, bladder and urethra) urine.

Kidney

• The main paired organ of the urinary system, responsible for the formation of urine.
• Each kidney contains about 1 million structural and functional units of the organ — nephrons.
• Parenchyma of the kidney is represented by epithelial elements of nephrons, stroma — connective tissue capsule, thin layers of loose connective tissue and a system of intraorgan blood vessels.
• Nephrons are naturally distributed throughout the organ, their various departments form the cortex and medulla of the kidney.
• A feature of the kidney vascular system is the presence of two capillary networks, through which blood flows sequentially to different parts of the nephron.
• Urine formed in the nephrons is excreted through a system of collecting ducts into the intrarenal urinary tract.

Functions:

• removal of metabolic products and foreign substances from the peripheral bloodstream (excretory function);
• regulation of water-electrolyte balance;
• endocrine (regulation of blood pressure, erythropoiesis processes).

The structure and blood supply of neurons

Kidney

Ultrastructure of the renal corpuscle

Ultrastructure of the nephrocytes of the proximal tubule

Vascular system of the kidney