Kidney Secondary

Secondary kidney - see Metanephros. Formed from the endoderm of the nephrogenic groove of the pharynx segment or the aortic thickening passing along the dorsal side of the pharynx, in the area of ​​the dorsomedial fork of the esophagus. Average length 4-5 mm; the lateral ends are underdeveloped and do not reach the inner surfaces of the anterior nasal processes. In the posterior part of the kidney there are remains of a pharyngeal or gastric outgrowth, tip, or a lymphoid cord develops. The kidney ends blindly and expands slightly in the forward direction. The epithelium of the surface layer is represented by a continuous layer of stellate cells. The number of metanephrons is significantly less than the parenchyma of the metanephrological system.