Retrieved from https://studentshare.org/biology/1674460-human-production
https://studentshare.org/biology/1674460-human-production.
At puberty, the kiss1 gene activates GPR54 gene which then activates hypothalamus to produce GnRH (gonadotropin-releasing hormone); a hormone that stimulates pituitary gland to produce hormones that affect testicles and ovaries. In males, testosterone is produced that affects the development of testes and penis along with the development of secondary sexual characteristics. In females, estradiol is produced by ovaries and it brings about the development of reproductive system and secondary sexual characteristics.
An additional effect is the onset of menarche. 6. Spermatogenesis may be divided into three phases: spermatocytogenesis which is a proliferative phase; meiosis which produced cells containing half number of chromosomes and spermiogenesis (mitosis allows division of spermatogonia and they develop into primary spermatocytes and during Meiosis 2 secondary spermatocytes are produced) in which spermatozoa are produced. Seminiferous tubules allow spermatozoa a channel to pass through. Spermiogenesis comes to an end when spermatozoa are released from sertoli cells.
Androgen (testosterone) is produced by Leydig cells. 7. Sperms are produced within seminiferous tubules from where they migrate to epididymis. They are stored here until maturation. During ejaculation, the sperm travel from epididymis to vas deferens, the ampulla. At this point other secretions are added to the sperms and the mixture is then propelled towards the ejaculatory duct and then while passing through urethra prostrate gland’s secretions is added. The combination of all these products is now known as semen which takes on a milky color; a secretion that is then expelled out of the body.
Uterus is made up of layers of smooth muscle and it is hollow from within. It consists of an isthmus, cervix, fundus and a body. During menstruation, the inner lining show growth of tissue; preparation of the uterus for implantation if
...Download file to see next pages Read More