Describe the structure of a seminiferous tubule.

The seminiferous tubule is a highly coiled structure, located in testicle lobules, where the production of sperms occurs and the process is called as spermatogenesis. Each seminiferous tubule is lined by germinal epithelium, on the inner side it is lined by two types of cells called i) spermatogonia – male germ cells that produce primary spermatocytes by meiotic divisions forms secondary spermatocytes which again undergoes meiotic division to form spermatids, that metamorphoses into male gametes called spermatozoa. ii) Sertoli cells – are also called as nurse cells of the testis as they provide nourishment to the germ cells. They are large and polygonal also called as interstitial or leydig cells, these cells secrete the male hormone called testosterone.

Diagrammatic representation of a seminiferous tubule as below:



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