Semen
Encyclopedia : S : SE : SEM : Semen
It is secreted by the gonads (sexual glands) of male or hermaphroditic animals, including slugs, for fertilization of female ova. Semen discharged by an animal or human is known as ejaculate, and the process of discharge is called ejaculation. Like blood, semen consists of two parts, the cellular part (spermatozoa and in some instances leucocytes and epithelial cells) and noncellular part (seminal plasma).
Depending on the species, spermatozoa can fertilize ova externally or internally. In external fertilization, the spermatozoa fertilize the ova directly, outside of the female's sexual organs. Female fish, for example, spawn ova into their aquatic environment, where they are fertilized by the semen of the male fish.
During internal fertilization, however, fertilization occurs inside the female's sexual organs. Internal fertilization takes places after insemination of a female by a male through copulation. In low vertebrates (amphibians, reptiles, birds and monotreme mammals), copulation is achieved through the physical mating of the cloaca of the male and female. In marsupial and placental mammals, copulation occurs through the vagina.
Mammalian semen is a whitish, milky fluid, very viscous, containing water and small amounts of salt, vitamin D, protein, and fructose. The plasma portion of semen may contain dissolved water- and fat-soluble constituents, depending on the diet of the organism in question.
Composition of human semen
Approximately 200- to 500-million spermatozoa (also called sperm or spermatozoans), produced in the testes, are released per ejaculation. However, they make up only about 2–5% of the volume of semen. The bulk of the semen is composed of seminal plasma, the fluid portion of semen. This fluid is contributed by the accessory male reproductive organs. Some 60% of the volume of ejaculate is produced by the seminal vesicles, and most of the remainder is generated by the prostate. A small amount of viscous mucus secreted by the bulbourethral glands contributes to the cohesive jelly-like texture of semen.
Seminal plasma of humans contains a complex range of organic and inorganic constituents. They include metal and salt ions, sugars, lipids, steroid hormones, enzymes, prostaglandin hormones, amino acids and basic amines. The seminal plasma provides a nutritive and protective medium for the spermatozoa during their journey through the female reproductive tract. The normal environment of the vagina is a hostile one for sperm cells, as it is very acidic (from the native microflora producing lactic acid), viscous, and patrolled by immune cells. The components in the seminal plasma attempt to compensate for this hostile environment.
Basic amines such as putrescine, spermine, spermidine and cadaverine are responsible for the smell and flavor of semen. These alkaline bases counteract the acidic environment of the vaginal canal (which is harmful to sperm), and protect DNA inside the sperm from acidic denaturation. Salts and metal ions in the semen help to create a more hospitable environment for the sperm in the vaginal canal. A typical ejaculation can contain up to 5 mg of zinc. Zinc serves to help to stabilize the DNA-containing chromatin in the sperm cells. A zinc deficiency may result in lowered fertility because of increased sperm fragility. Zinc deficiency can also adversely affect spermatogenesis.
The simple sugar fructose is the main energy source of sperm cells, which rely entirely on sugars from the seminal plasma for energy. Other components of semen (mucus and texturizing proteins) serve to increase the mobility of sperm cells in the vagina and cervix by creating a less viscous channel for the sperm cells to swim through, and preventing their diffusion out of the semen. Prostaglandin hormones are involved in suppressing an immune response by the female against the foreign semen.
If human semen is left in an open container for a few days, it begins to go bad and produce a distinctive smell similar to the pollen of the Tree of heaven.
Semen and transmission of disease
The semen of a disease-free individual is harmless on the skin . However, semen can be the vehicle for many sexually transmitted diseases, including HIV, the virus that causes AIDS. It is also hypothesized that components of semen, such as the spermatozoa as well as the seminal plasma, can cause immunosuppression in the body when introduced to the bloodstream or lymph. Evidence for this dates back to 1898, when Elie Metchnikoff injected a guinea pig with its own and foreign guinea pig sperm, finding that an antibody was produced in response; however the antibody was inactive, pointing to a suppression response by the immune system. Further research, such as that by S. Mathur and J.M. Goust, demonstrated that non-preexisting antibodies were produced in humans in response to the sperm. These antibodies mistakenly recognized native T lymphocytes as foreign antigens, and consequently the T lymphyocytes would fall under attack by the body's B lymphocytes.Other semen components shown to spur an immunosuppressive effect are seminal plasma and seminal lymphocytes.
Blood In The Semen (
The presence of blood in the semen may be undetectable (it only can be seen microscopically) or visible in the fluid.
Its cause could be the result of inflammation, infection, blockage, or injury of the male reproductive tract or a problem within the urethra, testicles, epididymis and prostate.
Further semen analysis and other uro-genital tests might be needed to find out the cause of blood in the semen.
Cultural views
According to some forms of taoism, Polynesian beliefs, and the so-called sex magic espoused by Samael Aun Weor and his Gnostic Movement (unrelated to the ancient Christian belief known as gnosticism), the "spilling" of semen is associated with loss of power and manly strength. In over 60 books including The Perfect Matrimony, Samael Aun Weor has argued that in order to activate and harness his kundalini energy, a man should never spill his semen.
Sacred semen
In pre-industrial societies, semen and other body fluids were revered because they were believed to be magical. Blood is an example of such a fluid, but semen was also widely believed to be of supernatural origin and effect and was, as a result, considered holy or sacred.At one time, it was believed that a woman’s menstrual blood formed the human soul and that mothers, therefore, were the source of the souls that animated their children.#redirect As the matriarchy gave way to the patriarchy, this idea was replaced with the notion that sperm creates the soul.
Dew was once thought to be a sort of rain that fertilized the earth and, in time, became a metaphor for semen. The Bible employs the term “dew” in this sense in such verses as Song of Solomon 5:2 and Psalm 110:3, declaring, in the latter verse, for example, that the people should follow only a king who was virile enough to be full of the “dew” of youth.
It was widely believed, in ancient times, that gemstones were drops of divine semen which had coagulated after having fertilized the earth. The Chinese believed that jade, in particular, was the dried semen of the celestial dragon and caressed the gemstone to feel close to the source of life.
Based upon the resemblance of dandelion juice to human semen, it was believed that the flower magically promoted the flow of sperm.
The orchid’s twin bulbs were thought to resemble the testicles, and the ancient Romans believed that the flower sprang from the spilled semen of copulating satyrs.
Barbara G. Walker recounts these examples of sacred semen in The Woman’s Dictionary of Symbols and Sacred Objects, the thesis of which is that myth and folklore show a pre-patriarchic rule by women that was later supplanted by masculine culture.
Semen In Popular Culture
Depiction of semen in art and popular culture, for a long time, is always considered as a taboo subject. Only recently semen has been depicted (albeit controversially) in movies such as American Pie or There's Something About Mary.
Andres Serrano, whose photos depict bodily fluids such as "Blood and Semen II" (Semen y Sangre II) (1990) became a controversial figure for featuring semen in his work. He was criticized by some for producing offensive art, while others defended him in the name of artistic freedom.
Euphemisms
Because sexual topics are often an uncomfortable topic among peers, a huge variety of euphemisms and dysphemisms have been invented to describe semen. For a complete list of terms, see: Sexual slangSee also
- ejaculation
- spermatozoon
- spermatogenesis
- bukkake
- pre-ejaculate
- capacitation
- sexual slang for a list of various commonly used terms for semen.
References
- Herdt, Gilbert H., Ritualized Homosexuality in Melanesia. Berkeley: University of California Press, 1993. ISBN 0520080963.
- Mann T, Lutwak-Mann C. 1981. Male Reproductive Function and Semen. Berlin: Springer-Verlag. ISBN 3-540-10383, 0-387-10383.
- Shivaji S, Scheit K-H, Bhargava PM. 1990. Proteins of seminal plasma. New York: John Wiley & Sons. ISBN 0-471-84685-6.
External links
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