Penis Research and Penis Enlargement

ANATOMY OF THE TESTICLES

The penis and the scrotal pouch (Latin: scrotum), holding the testicles (balls, eggs (Ger.)), together constitute a token that characterizes the male human. The word testicle does have something in common with the word testament. The Latin word testis also means witness; in Roman days, someone without testicles was definitively not a man and could therefore not testify.
The scrotal pouch is in fact a relatively simple pouch, made of rather thin skin, but with a definite muscle sheet underneath - that is the reason why, if necessary, the scrotal pouch can make itself somewhat smaller. Inside, the pouch is divided into two smaller pouches, each containing one testicle with its epididymis. An epididymis is connected to the testicle and overlies it like a cap; it contains a very large amount of microscopically small tubes. From the epididymis, the vas deferens will conduct the freshly made sperm cells to the area of the prostate. The vas deferens runs together with blood vessels that supply blood to and from the testicle and some muscle fibers; as a sort of long thin sausage they perforate the abdominal wall at the groin. Since, from the standpoint of the abdomen, the testicles are located 'outside' the body, there must be a tiny hole in the abdominal wall there to let the vas deferens in: early, or later in life, a hernia may form at this weak spot. Right behind the prostate the vas deferens joins the outlets of the seminal vesicles to be able to leave the body through the urethra as semen, in search of a female egg cell.

FUNCTION

Like so many other organs in our body, the testicle has its identical counterpart - one never knows, mother nature must have thought. The left and right testicle (plus everything that goes with it) have exactly the same function. Unlike what some people think, nothing is held in reserve; both testicles are active, although, in normal circumstances, one testicle is suffi cient.
The testicles have two functions:

The production of testosterone, the male sex hormone. A hormone is a substance, a molecule, that acts as a messenger in the blood. Since the blood flows through the entire body, the hormone in it will also reach every spot in the body; some organs, that are susceptible to the hormone, will then be told to do something. Testosterone will cause a boy to change into a man during puberty: he will grow a beard, his voice will get a lower pitch, his penis will grow, he will be able to have erections and will develop feelings of (male) lust. Of course, it is clear at a younger age that the child is a boy and not a girl (that difference is coded into the genes), but only after puberty started off - in girls usually somewhat earlier than in boys -, the hormone production is increased and male characteristics enhanced. Later in life, the hormone production will remain relatively constant, although it wears off at old age. Despite a lot of positive effects of testosterone, there also exist negative ones: it causes baldness in some men and may lead to growth of the prostate and may play a role in the development of prostate cancer. The level of testosterone in the blood varies from day to day and from one man to another. A higher testosterone level does not cause more feelings of lust, nor a bigger penis, nor a higher chance to develop can cer.
Hormones are usually needed in very small quantities - testosterone is no exception; without too much problems, one testicle can be missed - the other will produce sufficient amount of testosterone.
There exist, however, other male sex hormones in the body, which play a lesser role; these hormones are made in the adrenals, which also produce - in males too - female sex hormones.
Other cells inside the testicle are responsible for the production of sperm cells, millions each day. Production od sperm cells will continue day and night, so not only during ejaculation. The sperm cells can, however, be temporarily stored behind the prostate in the seminal vesicles. Sperm cells will last a long time; most cells in the semen are some two months old. After ejaculation, it takes about three days to get the semen back to normal (numbers of sperm cells) again.
Sperm cells are self-supporting and have their own engine in the form of a twisting tail. In the head of the sperm cell half of the total amount of genetic information needed to build a complete human is stored; the other half is supplied by the female egg cell. The production of sperm cells is 'on full ahead' all day long, while one cc of semen can easily contain 40 million sperm cells or more. Quality control is something to be desired, however, since about half the amount of sperm cells are not built well or malfunction; obviously, mother nature thinks that quantity is more important than quality - only one sperm cell is needed to mix with the female egg cell.
After a sperm cell ha been made in the testicle, it will need to grow into an adult cell, capable of fertilizing the egg cell; this maturation process takes place in the labyrinthine tube system of the epididymis. Harboring the maturation process of the immature sperm cell is the only function of the epididymis. When the sperm cell has grown up, it is further transported through the vas deferens in the direction of the prostate.

Beneath the skin of the scrotal pouch and in the stem that contains the vas deferens and blood vessels towards the testicle a lot of tiny muscle fibers can be found. If the testicles (and with it, fertility) are in danger, for example in extreme cold, but also in fright, these muscles come into play and contract; this causes the scrotal skin to ripple and get thicker, while the testicles are pulled up close to the warm and protecting body.
It is still not clear why mother nature has placed the vulnerable testicles more or less outside the protective body. Probably it has something to do with the production of sperm cells, which is perhaps more efficient while the temperature in the testicles is a bit lower than 37 degrees Celsius.