Semen

In most vertebrates, including amphibians, reptiles, birds and monotreme mammals, copulation is achieved through the physical mating of the cloaca of the male and female.

[2][4] During the process of ejaculation, sperm passes through the ejaculatory ducts and mixes with fluids from the seminal vesicles, the prostate, and the bulbourethral glands to form the semen.

The seminal vesicles produce a yellowish viscous fluid rich in fructose and other substances that makes up about 70% of human semen.

[6] Sertoli cells, which nurture and support developing spermatocytes, secrete a fluid into seminiferous tubules that helps transport sperm to the genital ducts.

Once the semen enters the ductus epididymis the principal cells, which contain pinocytotic vessels indicating fluid reabsorption, secrete glycerophosphocholine which most likely inhibits premature capacitation.

The components and contributions of semen are as follows: A 1992 World Health Organization report described normal human semen as having a volume of 2 mL or greater, pH of 7.2 to 8.0, sperm concentration of 20×106 spermatozoa/mL or more, sperm count of 40×106 spermatozoa per ejaculate or more, and motility of 50% or more with forward progression (categories a and b) of 25% or more with rapid progression (category a) within 60 minutes of ejaculation.

Blood in the semen can cause a pink or reddish colour, known as hematospermia, and may indicate a medical problem which should be evaluated by a doctor if the symptom persists.

[14] After a period typically ranging from 15 to 30 minutes, prostate-specific antigen present in the semen causes the decoagulation of the seminal coagulum.

[15] It is postulated that the initial clotting helps keep the semen in the vagina,[12] while liquefaction frees the sperm to make their journey to the ova.

[12] A 2005 review found that the average reported viscosity of human semen in the literature was 3–7 centipoises (cP), or, equivalently, millipascal-seconds (mPa·s).

This includes transmission risk for sexually transmitted infections such as human papillomavirus or herpes, especially for people with bleeding gums, gingivitis or open sores.

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 or prostate.

It usually clears up without treatment, or with antibiotics, but if persistent further semen analysis and other urogenital system tests might be needed to find out the cause.

[27][28] Among numerous species in the animal kingdom, females may benefit from absorbing nutrients and proteins from seminal fluid for food, antiviral and antibacterial properties, and enhanced fertilisation.

In humans, seminal fluid provides anti-viral activity towards herpes simplex virus and can transfer anti-microbial peptides cathelicidin and lactoferrin.

[20] Qigong and Chinese medicine place huge emphasis on a form of energy called 精 (pinyin: jīng, also a morpheme denoting "essence" or "spirit")[29][30] – which one attempts to develop and accumulate.

[34][35] The connection between bodily heat (tapas) and sexual desire (kama) is not just metaphorical but is found to be rooted in physiology, "All adolescent and fertile adults are hot.

[36]: 126 Women, in general, are deemed as relatively more hotter than men, partly due to menstruation and pregnancies, which result in higher concentrations of blood to the womb.

[36]: 127  Though excessive heat in a woman is synonymous with "shakti and latent fertility", it is potentially dangerous and must be restrained, lessened and transmuted.

This is sought to be achieved by "binding", wherein women wear tight upper clothing, bangles and necklaces; and "sealing the body" in oil baths and herbal powders; and through regular sexual intercourse.

Drinking lots of Water and proper digestion of highly nourishing foods (milk, ghee, nuts) yield healthy shukra.

Indulgence in sexual activity is healthy for stronger individuals, but in weaker people it weakens them further, and is sought to be alleviated by abstinence as it restores shukra, which is always produced as a result of the digestion of food one eats.

"[41] This may be explained by the belief of the Pythagoreans that "semen is a drop of the brain [τὸ δε σπέρμα εἶναι σταγόνα ἐγκέφαλου].

"[42] Greek Stoic philosophy conceived of the Logos spermatikos ("seminal word") as the principle of active reason that fecundated passive matter.

[43] The Jewish philosopher Philo similarly spoke in sexual terms of the Logos as the masculine principle of reason that sowed seeds of virtue in the feminine soul.

[51]: 32, 49  The Sumerians believed that rain was the semen of the sky-god An,[54] which fell from the heavens to inseminate his consort, the earth-goddess Ki,[54] causing her to give birth to all the plants of the earth.

[57] When the British Secret Intelligence Service discovered that semen made a good invisible ink, Sir Mansfield George Smith-Cumming noted of his agents that "Every man (is) his own stylo".

In Baruya culture, there is a secret ritual in which boys give fellatio to young males and drink their semen, to "re-engender themselves before marriage".

Slang terms for semen include cum, jism (also shortened to jizz), spunk (primarily British English), spooge and/or splooge, load, nut, seed, and love juice.

Spermatozoa , in this case human, are a primary component in normal semen, and the agents of fertilization of female ova .
Human semen in a Petri dish
Semen stain on carpet observed with and without ultraviolet light
An illustration of gokkun
An Illustration of snowballing