Penis is the reproductive organ of a man which hangs down in front of a pouch of skin called scrotum containing two testes.

Tip of the penis has a head like structure called glans covered by skin called foreskin.

A greasy substance called smegma secreted under this foreskin facilitates its movement over the glans.

Accumulation of smegma can cause inflammation.  Therefore every person must wash this part regularly by moving the foreskin backward. However, this is not essential for infants..

In some individuals, foreskin is removed for religious purpose.

The head of the penis is extremely sensitive to touch due to its rich nerve supply.

Penis consists of a central tube called urethra which helps in passing out urine collected in the bladder.  The same tube also carries fluid called semen containing sperms during ejaculation for reproductive purpose or self pleasuring.

Penis has band of erectile tissues which help in erection of penis.

Boys at the same age may look different; even their pubic hair growth may vary from absent to full. But, their penis is almost of the same size.

The main length of the penis is called body or the shaft and its attachment to the abdomen is a root of the penis.

The penis does not contain any muscles and its size cannot be changed by any cream or massage or device and there is no need whatsoever to change it.

Nor it is true that bigger penis makes better lover.

Even if the men of the same age look different in structure due to their ethnic origin, their penis is almost of the same size.

Penises appearing different in flaccid position are more or less of the same size on erection. The penis that looks smaller can reach adequate length on arousal.

Size of the penis is measured from the base along the upper border to the tip.

One may find his penis smaller if it is seen from above.  For better impression, one should look in mirror in full front position.

Scrotum

Scrotum is a pouch of skin which contains testes and it hangs directly under the Penis.

The scrotal pouch is made of several layers of tissues along with thin coat of ‘cremasteric muscles’. This muscle coat plays important role in controlling temperature around the testes 1 to 2 degrees below the body temperature, which is required for proper formation of healthier sperms.

While in fear or in cold environment, these cremasteric muscles contract to elevate the testes and bring them closer to body heat. They relax in warm environment to lower the testes away from the body heat.  Here, the Pampiniform Plexus of veins around the arteries supplying blood to testes acts as a thermoregulatory mechanism to keep the testes cooler than body temperature.

The scrotal pouch contains two testicles

Like penis, testes are also important part of the male reproductive system.

Testes release male sex hormone to produce sperms which carry genetic information of the person to the offspring and maintain the male characteristics such as deep voice, male hair distribution and typical distribution of fat.

Size of both the testes differs and usually the left one hangs down more.  Both the testes are suspended in the scrotum by a spermatic cord surrounded by a tube of muscle called cremastin muscle.  With the help of contraction of these muscles, upward movement of testes take place.

Such movement is helpful in maintaining the temperature around testes.

In the cold weather they are drawn upwards near the body for warmth.  In hot surroundings their blood supply increases to control the temperature.

Contraction of these muscles causes upward movement of testes during intercourse.

Sperms are manufactured best at a temperature of 1 or 2 degrees less than body temperature, therefore testes are placed in scrotum away from the abdominal temperature.

Hot water bath or wearing tight clothes reduce sperm production. It is advisable to wear loose clothes at night.

The other important function of testes is to release hormone called ‘testosterone, which controls male sexual development like growth of hair, voice breaking, fat distribution and other male characteristics. Most importantly it develops sexual desire in men.

Pampiniform Plexus

The network of veins surrounding the artery supplying blood to each testicle, is called Pampiniform Plexus.

This acts as a thermoregulatory mechanism to keep the temperature of the testes below the body temperature.

This mechanism works by creating counter-current system so that heat of the artery is absorbed by the veins.

Thus temperature of the testes is kept lower than body temperature. This difference in temperature is essential for formation of  sperms.

In men, by wearing tight undergarments or by exposing testes to hot water repeatedly, the heat around testes leads to low sperm count often causing infertility.

These men may have normal quantity of semen while ejaculating, but the ejaculated semen contains less sperms, which may be insufficient for achieving pregnancy.

Epididymis is a highly coiled network tubules folded against back of the surface of each testes.

Sperms which are produced in seminiferous tubules located in testes are emptied into epididymis.

Here the sperms spend several weeks moving slowly through the coils of epididymis as they reach their full maturity.

For ejaculation, the matured sperms are carried through vas difference, the tubes from each testicle, to ejaculatory duct where seminal fluid joins it from seminal vesicles and further joined by secretion of prostate gland to make remaining part of semen, which is then ready to get ejaculated.

Vas Difference are the tubes that run from each testes and join duct from seminal vesicle to form the ejaculatory duct.

Seminal Vesicles are pair of glands that produce seminal fluid and release them into ejaculatory duct to join sperms arrived through vas difference.

Vas Difference are about 18 inches long and carry matured sperms from the epididymis to be poured into a ejaculatory duct where secretion from seminal vesicle duct forms 70 % of the semen. This short straight ejaculatory duct then passes into prostate gland where remaining 30 % of the fluid is added to the semen.

The fluid secretion from seminal vesicles give nourishment to sperms while alkaline secretion of prostate gland neutralizes the acidic environment of male (urethra) and female (vagina) reproductive tracts. 

Cowper’s Glands, also called Bulbo-urethral glands, are two pea sized glands under the Prostate gland which secrets a clear alkaline fluid into the urethra during sexual arousal before orgasm and ejaculation.

Urethral track which is primarily used for passing of urine is now being prepared for passing of semen for ejaculation.

This mucous like pre-ejaculatory fluid or pre-cum has a function of removing acidity of the urethral passage and lubricating the urethra for semen to ejaculate.

Prostate gland is a walnut shaped structure (organ) present only in men, which is situated at the base of the bladder and surrounds the urethra.

This gland produces the fluid that mixes with semen to make up part of the seminal fluid.

This secretion is believed to be helpful in motility of sperm. That is, it makes sperm active for their journey from vaginal cavity up to Fallopian Tubes through Uterine cavity..

Any swelling of this gland can directly lead to compression of the urethra, thereby developing difficulty in passing urine. This is more common in elderly persons.

Any swelling of prostate should be investigated thoroughly to rule out cancer.

Sperms are produced in tightly coiled microscopic tubules called seminiferous tubules present in each testicle.

The entire process of sperm production takes about seventy days.

These sperms than travel to coiled structure called epididymis present at the back of the testes till they get matured.

The matured sperm are then transported via tube from each testes called vas difference to form important part of the semen.

Unlike females who have all the eggs present at birth to be matured on puberty one at a time, in men sperm production begins only at puberty.

Sperms live for about 40 days and if unused for ejaculation get disintegrated in the body harmlessly.

Semen

On an average quantity of semen per ejaculate is about one teaspoonful (3 to 5 ml).

Although the quantity of sperm in each ejaculate may vary in each person and even on different occasions depending on age of a person, frequency of ejaculation and other factors. However, sperm count of 40 to 120 million per millilitre of semen is considered normal.

That means about 120 to 600 million sperm could be present in each ejaculate.

Seminal fluid which makes 70% of the fluid quantity of semen, is a whitish to grey colour and creamy and sticky texture.

At the time of ejaculation, the semen is thick in consistency, but gets liquefied quickly thereafter.

It contains water, mucous, sugar along with some chemicals which provide nourishment and energy to sperms. Semen also contains secretion from Prostate gland which neutralizes acidity of male urethra and female vagina and the prostaglandin hormone that causes contractions in uterus and Fallopian tubes for facilitating upward journey of sperms towards matured egg placed at the end of one of the two Fallopian tubes.

Smegma

In uncircumcised penis, when the foreskin is rolled back, tiny bumps are seen at the base of the glans (head) of the penis.

These are glands that produce a white creamy substance called Smegma, which gathers naturally under the foreskin for smooth gliding of the foreskin.

Boys should be trained to glide back their foreskin and clean the surface of glans regularly while taking bath. Otherwise, this smegma accumulates under the foreskin along with dead skin cells, dirt particles, sweat and bacteria creating an unhygienic condition causing inflammation, bad smell and infection.

Habit of cleaning the area under the foreskin should continue even during adulthood.

Retracting foreskin is not recommended for infants.

In circumcised men, the smegma does not collect, as the glans is open and gets cleaned easily.

Of all the parts of the body, the part which worries most men is size of their penis, whether the individual is 15 or 50

Size of the penis size is probably more of an issue during puberty than during adult life. Because boys mature at different rates, boys of the same age will naturally show variation in penis size.

The boys also get plenty of chances to compare penis size in changing room or when they discuss in private.

It is true that, when soft, not all penises are the same length, although they are generally between 8 and 11 cm (3 – 4 in) in length. But when erect, most penises are between 12 and 17 cm (5-7in) long from base to tip.

During erection smaller penises increase proportionately more in size than larger penises.

Most boys (and men) often view their own organ by looking down at it, which makes it seem shorter. Whereas they inspect other boys’ penises from the front or side, which naturally makes others’ penises look longer in comparison. To evaluate the correct size of their penis boys should view in the mirror.

Boys who are overweight may think that they have a small penis, but it is probably their penis of normal length is ‘buried’ under the mound of fat around its base.

The greatest damage, however, is probably done when boys or even men discuss over this topic and establish the thousands of year old misconception that larger penis is an indicator of sexual ability and manliness.

In reality, penis size has little to do with how many erections or orgasms you can have, or whether you can satisfy your partner during sexual intercourse.

Most women are least bothered about size of the penis. Many don’t even prefer to touch it unless required for guiding its insertion into the vagina.

Women get sexual pleasure when a man they love spends time and attention to get her sufficiently aroused before insertion of penis. Woman aroused properly has well lubricated vagina for better movements of penis. Well aroused woman can grip even the smaller size penis and participates in sexual intercourse with series of contractions of vaginal walls and pelvic muscles making it mutually satisfactory.

Size of the penis does not matter much in this pleasurable moment. But, worrying about it can definitely affect hardness of erection and spoil the show altogether.