Path: typhoon.sonic.net!out.nntp.be!propagator-dallas!news-in-dallas.newsfeeds.com!in.nntp.be!feed2.onemain.com!feed1.onemain.com!cyclone-sf.pbi.net!206.13.28.183!nnrp5-w.sbc.net.POSTED!ssg.uncanny.net!robomod!not-for-mail From: "Reka Morvay" Newsgroups: soc.sexuality.general Subject: Re: what is semen composed of? Organization: Cornell University Lines: 49 Sender: ssg@atlantic.devin.com Approved: SSG Approval Key Message-ID: <9cuik8$sj$1@news01.cit.cornell.edu> References: <0472d3e7a85f036014e032c6e0bec276@anon.xg.nu> <3AE7066C.CC7C1E15@home.com> X-SSG-Policy: http://www.uncanny.net/~ssg X-SSG-Info-1: Send submissions to ssg@uncanny.net X-SSG-Info-2: Send technical complaints to ssg-admin@uncanny.net X-SSG-Info-3: Send complaints about policy to ssg-board@uncanny.net X-Comment: moderators do not necessarily agree or disagree with this article. X-Robomod: STUMP, ichudov@algebra.com (Igor Chudov), C++/Perl/Unix Consulting X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4522.1200 X-Auth: PGPMoose V1.1 PGP soc.sexuality.general iQBVAwUBOvLNvRjLI1hTTLWlAQHY/AH/aVrVOdCcaxHd7rpS0bfTIdjOd2+mRJFW 452yf1U0Hu82j3S/ZoEv07fZdYHrxy8wwvZH+fYijvlPkqitxgs9Hg== =Mic+ Date: 4 May 2001 08:44:07 -0700 NNTP-Posting-Host: 63.197.80.100 X-Complaints-To: abuse@pacbell.net X-Trace: nnrp5-w.sbc.net 988991048 63.197.80.100 (Fri, 04 May 2001 08:44:08 PDT) NNTP-Posting-Date: Fri, 04 May 2001 08:44:08 PDT Xref: typhoon.sonic.net soc.sexuality.general:28531 Semen is a mixture of fluids contributed by a number of different glands. About half the volume is supplied by the seminal vesicles, a third is prostatic fluid, and the rest is mostly epididymal fluid with the sperm. The Cowper's gland contributes a negligible amount of mucous fluid. The volume of a typical ejaculate is 2-6 mL, which is about one teaspoon. A "serving" of semen has 7-25 calories. Below is a breakdown of the components of each fluid: Epididymal fluid: =========== - carnitine: inhibits sperm motility (this is important while the sperm are stored in the epididymis) - chemicals that inhibit the activation of acrosomal enzymes in the sperm. Acrosomal enzymes, when activated, are responsible for drilling into the egg. It's important that these enzymes remain inactive while the sperm is still in the man's body, otherwise they'd drill through the epididymis. In fact, these enzymes are only activated by chemicals that are released near/with the egg by cells in the woman's body. - sperm Seminal vesicle fluid ============== - fructose: the function of fructose in seminal vesicle fluid is unclear. It may be important in aquatic animals that fertilize externally. - NaHCO3: a base that acts to neutralize the acidity of the vagina - ergothionine: may activate sperm motility - prostaglandins: may serve some function in the female body, by promoting contractions of the uterus and oviducts that aid the transport of sperm. Low levels of prostaglandins lead to infertility. - fibrogen-like clotting protein: semen clots to a jelly-like consistency Prostatic fluid ========= - zinc: prostatic fluid has a very high zinc concentration, comprising 60-70% of its dry weight. Low zinc concentrations lead to infertility. - sodium citrate: provides an immediate source of energy for sperm - enzymes: activate the coagulation process of the clotting proteins in the seminal vesicle fluid - acid phosphatase: activates sperm - polyamines (spermine and spermidine): activate sperm motility, kill bacteria, and provide the characteristic odor of human semen With thanks to my undergraduate human reproductive biology professor at Berkeley. Reka