What's the origin of intermediate mesoderm?

Answer:The intermediate mesoderm is a germ layer aptly named for its intermediate position between the paraxial and lateral plate mesoderm. The paired cylindrical masses of the intermediate mesoderm are arranged along the posterior aspect of the embryo, laterally to the paraxial mesoderm.

Step-by-step explanation:The intermediate mesoderm develops into the urogenital system, which includes the kidneys and gonads, and their respective duct systems, as well as the adrenal cortex. The intermediate mesoderm forms paired elevations called urogenital ridges. The nephric duct arises from intermediate mesoderm and is essential for all further urogenital development. In the third week of fetal development, the intermediate mesoderm differentiates into the kidneys. Three pairs of kidneys successively form within the intermediate mesoderm: the pronephros, the mesonephros, and the metanephros, where the last pair persists as the functional kidneys of the newborn.

The intermediate mesoderm comes to lie in parallel ridges in the roof of the intraembryonic coelom on either side of the midline in the thoracic and abdominal regions. These ridges, known as the urogenital ridges, later form both the excretory and the reproductive organ systems.