spermatogenesis

Examples of spermatogenesis in the following topics:

• Hormonal Regulation of the Male Reproductive System

  • Hormonal control of spermatogenesis varies among species.
  • However, it is known that initiation of spermatogenesis occurs at puberty due to the interaction of the hypothalamus, pituitary gland, and Leydig cells.
  • If the pituitary gland is removed, spermatogenesis can still be initiated by follicle-stimulating hormone (FSH) and testosterone.
  • The Sertoli cells themselves mediate parts of spermatogenesis through hormone production.
  • The sequestering of testosterone in the testes is initiated by FSH, and only testosterone is required to maintain spermatogenesis.

• Spermatogenesis

  • Spermatogenesis is the process by which male primary sperm cells undergo meiosis and produce a number of cells calls spermatogonia, from which the primary spermatocytes are derived.
  • Spermatogenesis is the male version of gametogenesis and  results in the formation of spermatocytes possessing half the normal complement of genetic material.
  • Spermatogenesis, essential for sexual reproduction is highly dependent upon optimal conditions to occur correctly.
  • Instead, certain types of spermatogonia divide to produce copies of themselves, thereby ensuring a constant supply of gametogonia to fuel spermatogenesis.
  • Spermatogenesis is highly sensitive to fluctuations in the environment, particularly hormones and temperature.

• Gametogenesis (Spermatogenesis and Oogenesis)

  • Spermatogenesis and oogenesis are both forms of gametogenesis, in which a diploid gamete cell produces haploid sperm and egg cells, respectively.
  • The production of sperm is called spermatogenesis and the production of eggs is called oogenesis.
  • Spermatogenesis occurs in the wall of the seminiferous tubules , with stem cells at the periphery of the tube and the spermatozoa at the lumen of the tube.
  • During spermatogenesis, four sperm result from each primary spermatocyte, which divides into two haploid secondary spermatocytes; these cells will go through a second meiotic division to produce four spermatids.

• Male Hormones

  • The onset of puberty is controlled by two major hormones: FSH initiates spermatogenesis and LH signals the release of testosterone.
  • FSH enters the testes, stimulating the Sertoli cells, which help to nourish the sperm cells that the testes produce, to begin facilitating spermatogenesis.
  • Testosterone, the hormone responsible for the secondary sexual characteristics that develop in the male during adolescence, stimulates spermatogenesis, or the process of sperm production in the testes.
  • This inhibits the release of GnRH and FSH, which will cause spermatogenesis to slow down.
  • GnRH stimulates the production of FSH and LH, which act on the testes to begin spermatogenesis and to develop secondary sex characteristics in the male.

• Testes

  • Thee testes produce sperm (spermatogenesis) and androgens, primarily testosterone.
  • The presence of both testosterone and follicle-stimulating hormone (FSH) is needed to support spermatogenesis.
  • They also support libido, spermatogenesis, and erectile function.
  • The sertoli cells are the testes’ somatic cells, necessary for testis development and spermatogenesis.

• Male and Female Gonads

  • The primary functions of the testes are to produce sperm (spermatogenesis) and androgens, primarily testosterone.
  • The presence of both testosterone and follicle-stimulating hormone is needed to support spermatogenesis.

• Anatomy of the Male Reproductive System

  • Within these tubules, spermatogenesis takes place.