The
epithelium of the tubule consists of a type of
sustentacular cells known as
Sertoli cells, which are tall, columnar type cells that line the tubule. In between the Sertoli cells are
spermatogenic cells, which differentiate through
meiosis to
sperm cells. Sertoli cells function to nourish the developing sperm cells. They secrete
androgen-binding protein, a binding protein which increases the concentration of testosterone. There are two types: convoluted and straight, convoluted toward the lateral side, and straight as the tubule comes medially to form ducts that will exit the testis. The seminiferous tubules are formed from the testis cords that develop from the primitive
gonadal cords, formed from the
gonadal ridge. ==Function==