Gonads, Male: Cell Types Composing the Tissue

The male gonad consists of the two testicles, or testes, that are involved in the production of sperm and testosterone. The gonads arise from two types of cells in the embryo: (1) the primordial germ cells (PGC) that originate in the ectoderm and are responsible for the formation of sperms and oocytes and (2) the somatic cells that surround and nourish the PGC.

The testicles originate as a bipotential primordium from a single layer of cells on the surface of the mesonephros. Whether the bipotential primordium will differentiate into a male or a female organ is dependent on the expression of the male specific transcription factor, Sry, in the Y chromosome. Sry lies upstream of male determining factors and morphogenetic programs, and is the master regulator ...