PATHOLOGY

Detailed explanation-1: -Adjacent to the pronephric ducts, the intermediate mesoderm will condense to form non-functional nephron units, known as pronephroi, which will regress by day 25.

Detailed explanation-2: -Pronephros is the earliest nephric stage in humans, and constitutes the mature kidney in most primitive vertebrates. Mesonephros develops by the formation of mesonephric tubules from the intermediate mesoderm, it is the principal excretory organ during early embryonic life (4-8 weeks).

Detailed explanation-3: -Pronephros is the most basic of the three excretory organs that develop in vertebrates, corresponding to the first stage of kidney development. It is succeeded by the mesonephros, which in fish and amphibians remains as the adult kidney.