Capacitation is the process of conditioning of sperms before fertilization that occurs within?
Ans. D. Female genital tract. (Ref Longman's Embryology 9th/pg. 38; Ganong 22nd/427).Longman's Embryology.9th/pg. 38........"Capacitation is a period of conditioning in the female reproductive tract that in the human lasts approximately 7 hours. Much of this conditioning, which occurs in the uterine tube, entails epithelial interactions between the sperm and mucosal surface of the tube. During this time a glycoprotein coat and seminal plasma proteins are removed from the plasma membrane that overlies the acrosomal region of the spermatozoa. Only capacitated sperm can pass through the corona cells and undergo the acrosome reaction".Spermatozoa are not able to fertilize the oocyte immediately upon arrival in female genital tract & must undergo:# Capacitation (glycoprotein coat and seminal plasma proteins are removed from spermatozoon head), and# Acrosome reaction, during which acrosin and trypsin-like substances released to penetrate the zona pellucida.Capacitation# Capacitation of sperm takes 2-6 hr.# Only the capacitated sperms can penetrate zona pellucida.# Once ejaculated into the female, the spermatozoa move up the uterus to the isthmus of the uterine tubes, where they slow down and undergo capacitation. This further maturation process involves two components:- Increasing the motility of the spermatozoa and- Facilitating their preparation for the acrosome reaction.# However, the role of capacitation appears to be facilitatory rather than obligatory, because fertilization is readily produced in vitro.# From the isthmuses the capacitated spermatozoa move rapidly to ampulla, where fertilization takes place.The phases of fertilization include: phase 7, penetration of the corona radiata; phase 2, penetration of the zona pellucida; and phase 3, fusion of the oocyte and sperm cell membranes.
Vas deferens
Epididymis
Seminiferous tubules
Female genital tract
Endocrinology and Reproduction