Metanephros, Kidney Secondary (Metanephros)

Metanephros, Kidney Secondary (Metanephros) - an excretory organ in the fetus that arises in the human embryo in the second month of embryonic development, from which the kidney is subsequently formed; The metanephros itself is formed from two sources: metanephrogenic tissue and the proximal end of the ureteric outgrowth of the duct of the primary kidney. Until the birth of the child, it does not function, since urea is removed from the fetal body, passing through the placenta surrounding it.

Metanephros is a secondary kidney that appears in human embryos in the second month of embryogenesis. It is an excretory organ and develops from metanephrogenic cells that are located in the metanephric substance. Metanephrogenic substance is a collection of cells from which nephrons and other structures of the kidney are formed.

Metanephrogenic tissue begins to develop in the 12th week of embryogenesis and continues to grow until the 20th week. During the second month of fetal development, metanephrogenic cells begin to differentiate into nephrons, which form the renal tubules.

Over the next few weeks, the connective tissue that forms the kidney capsule, as well as the blood vessels and nerves that provide nutrition and innervation to the kidney, develop.

By the time of birth, the kidneys are already fully formed and ready to perform their functions. However, until this moment, the metanephros does not perform any functions, since it does not have its own mechanisms for removing metabolic products from the body. Instead, urea and other waste products pass through the placenta, which ensures their removal from the mother's body.

Thus, metanephros plays an important role in the development of the kidney and the formation of its structure and function. However, it is not a full-fledged kidney and cannot perform all the functions that an adult kidney performs.

The metanephros, also known as the secondary kidney, is an excretory organ that forms in the human embryo during the second month of embryonic development. It first appears at the stage of embryogenesis and subsequently develops into a full-fledged kidney. Metanephros is formed from two sources: metanephrogenic tissue and the proximal end of the ureteric outgrowth of the duct of the primary kidney.

It is important to note that the metanephros does not function until the baby is born. This is due to the fact that urea leaving the fetus is removed from the body through the placenta. During pregnancy, the surrounding placenta performs the function of excreting waste and providing the fetus with everything it needs to survive and develop.

After birth, the metanephros begins to function and fulfill its main role in the child’s body. It plays an important role in regulating water-salt balance, filtering blood and removing waste through the urinary tract. Gradually, the metanephros develops into a full-fledged kidney with all its structural components, such as the cortex, medulla and ureters.

The formation of the metanephros is a complex and finely regulated process. It depends on the interaction of various genetic and molecular signals that control cell differentiation and migration, the formation of blood vessels and structural elements of the kidney. Disturbances in this process can lead to congenital kidney abnormalities and other genitourinary disorders.

Studying the development of metanephros is important for understanding kidney formation and preventing congenital kidney defects in newborns. This allows for the development of diagnostic and treatment strategies for such conditions, as well as the exploration of potential methods to regenerate and replace kidney function in the event of kidney damage or disease.

In conclusion, the metanephros, or secondary kidney, is an embryonic excretory organ that later develops into a full-fledged kidney. Its formation depends on complex genetic and molecular mechanisms, and its role is to regulate water-salt balance and remove waste from the body. Studying the development of metanephros contributes to the understanding of normal kidney formation and may lead to the development of new treatments and regeneration of renal tissue.