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Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testicle. This process starts with the mitotic division of the stem cells located close to the basement membrane of the tubules. [1] These cells are called spermatogonial stem cells. The mitotic division of these produces two ...
Sperm Spermiogenesis is the final stage of spermatogenesis , during which the spermatids develop into mature spermatozoa . At the beginning of the stage, the spermatid is a more or less circular cell containing a nucleus , Golgi apparatus , centriole and mitochondria ; by the end of the process, it has radically transformed into an elongated ...
The spermatogenesis process in mammals as a whole, involving cellular transformation, mitosis, and meiosis, has been well studied and documented from the 1950s to 1980s. However, during the 1990s and 2000s researchers have focused around increasing understanding of the regulation of spermatogenesis via genes, proteins, and signaling pathways ...
Another simple way to establish a female line for hybrid seed production is to identify or create a line that is unable to produce viable pollen. Since a male-sterile line cannot self-pollinate, seed formation is dependent upon pollen from another male line. Cytoplasmic male sterility is also used in hybrid seed production.
One view is that it is stuck with enzymes evolved in a colder temperature due to external testes evolving for different reasons. Another view is that the lower temperature of the testes simply is more efficient for sperm production. The classic hypothesis is that cooler temperature of the testes allows for more efficient fertile spermatogenesis.
Spermatogenesis is the process in which sperm cells are produced and formed into mature spermatozoa from spermatogonia. Males mature spermatozoa (sperm) are produced to later join with a female oocyte (egg) to create offspring. Throughout the process of spermatogenesis, there are many different parts of the male anatomy, accessory organs, and ...
Sertoli cells are a type of sustentacular "nurse" cell found in human testes which contribute to the process of spermatogenesis (the production of sperm) as a structural component of the seminiferous tubules. They are activated by follicle-stimulating hormone (FSH) secreted by the adenohypophysis and express FSH receptor on their membranes.
Anisogamy is the form of sexual reproduction that involves the union or fusion of two gametes which differ in size and/or form. [12] The smaller gamete is considered to be male (a sperm cell), whereas the larger gamete is regarded as female (typically an egg cell, if non-motile).