Functional Morphology of the Male Reproductive System

Abstract

The reproductive organs of males comprised of primary reproductive organs (testes), excurrent ducts composed of rete testis, vasa efferentia, epididymis, vas deferens, and urethra, accessory sex organs (seminal vesicle, ampulla, prostate and bulbourethral or Cowper’s glands), and ancillary organs (penis and prepuce). The primary functions of the testes are spermatogenesis and steroidogenesis. The Sertoli cells of the testes aid nutritional support to spermatozoa. The spermatozoa are transported through the excurrent duct and stored in the epididymis for their maturation. The spermatozoa are suspended in the seminal plasma produced from accessory sex organs. The hypothalamic–hypophyseal–gonadal (HPG) axis controls the functions of the testes and other reproductive organs. The HPG axis becomes fully functional at puberty with the activation of the GnRH surge centre and subsequently stimulates the anterior pituitary for FSH and LH secretion. The LH stimulates Leydig cell steroidogenesis. The Leydig cells produce testosterone which facilitates spermatogenesis within the seminiferous tubules. This chapter highlights the functional morphology of the male reproductive system and the factors controlling the functions of each organ. Puberty and its associated events are also discussed. The entire chapter is divided into five sub-chapters to understand different aspects of the male reproductive system.