Kidney development, or nephrogenesis, describes the embryologic origins of the kidney, a major organ in the urinary system. The development of the kidney proceeds through a series of successive phases, each marked by the development of a more advanced kidney: pronephros, mesonephros, and metanephros. During the fifth week of gestation, the mesonephric duct develops an outpouching, the ureteric bud, near its attachment to the cloaca. This bud, also called the metanephrogenic diverticulum, grows posteriorly and towards the head of the embryo. The elongated stalk of the ureteric bud, called the metanephric duct, later forms the ureter. As the cranial end of the bud extends into the intermediate mesoderm, it undergoes a series of branchings to form the collecting duct system of the kidney. It also forms the major and minor calyces and the renal pelvis.
Kidney development, or nephrogenesis, describes the embryologic origins of the kidney, a major organ in the urinary system. The development of the kidney proceeds through a series of successive phases, each marked by the development of a more advanced kidney: pronephros, mesonephros, and metanephros. During the fifth week of gestation, the mesonephric duct develops an outpouching, the ureteric bud, near its attachment to the cloaca. This bud, also called the metanephrogenic diverticulum, grows posteriorly and towards the head of the embryo. The elongated stalk of the ureteric bud, called the metanephric duct, later forms the ureter. As the cranial end of the bud extends into the intermediate mesoderm, it undergoes a series of branchings to form the collecting duct system of the kidney. It also forms the major and minor calyces and the renal pelvis.