Describe the structure of a seminiferous tubule.

Seminiferous tubules are a highly coiled structure where the production of sperms in the testes takes place. These tubules are located within the testicular lobules. The two types of cells namely spermatogonia and Sertoli cells are found in the germinal epithelial lining of seminiferous tubules. Spermatogonia produces primary spermatocytes by meiotic divisions which are male germ cells. Primary spermatocytes undergo further meiotic division to form secondary spermatocytes and eventually, spermatids. Spermatozoa are produced by the metamorphosis of the spermatids. Though the Sertoli cells provide nourishment to the germ cells, they are also referred to as nurse cells. The large polygonal cells known as interstitial cells or Leydig cells are present between the seminiferous tubules. Male hormone called testosterone is secreted by these cells.