We will get straight into the subject matter. If, any of you have doubts, I will do my best to clarify. Although I would like to remind the reader that I'm not a Physician. In every field, there are experts. One should respect, learn and seek advice from them. I do follow very 'authentic' text books. But when it comes to certain serious conditions that can threaten a person's life, one should always consult a Physician/Specialist to address the problem. Don't abuse the body. It is amazing how different body organs function and work as a team to keep the body in a stable state.
Male Reproductive Anatomy:
The Penis: The main organ that receives male attention is the penis. Even men are worried about and preoccupied with the size and shape of their penis. They also ask 'shouldn't it be bigger?'. Do the testicles hang properly? One thing everybody should be very clear is that 'appearance, in general, is nothing to do with functioning'. Only if a person is applying for jobs in strip clubs, appearance matters. The size of the penis has nothing to do with virility. Unfortunately, many men think women love larger penis, but penis size is a male concern. A woman would be more concerend about the strength of the erection than the size. A woman expects more of psycho-sexual experience from her man. A man can have larger testicles or penis but if, for God's sake, he develops cancer of that organ, he just has to forgo the organ to save his life. It applies to women too. So, don't confuse appearance with functioning.
Average length of the flaccid penis is 3 to 6 inches(some can be shorter or longer) and the erect penis is 4 to 8 inches. Human penis in relation to body size, is nothing compared to other animals. The Boar has a penis 1.5 feet long, the stallion has 2.5 feet, the bull has 3 feet, the elephant has 5 feet and the blue whale has 8 feet! One of my friend jokingly said he would like to be born as blue whale in his next birth:-) I wished him good luck!
Men who are overweight feels their penis is shrinking and becoming smaller. The reason is the excess fat is drooping over and gives a 'false' appearance. Actually, only half the penis hangs outside and the remaining half extends inside. It can be made to appear thicker & longer. It can be made to appear longer by cutting the ligament that holds it in the middle. It can also be made thicker by injecting one's own fat cells under the skin of the penis. But it is not permanent. Moreover, the surgeons may apply some irritants that may cause temporary swelling. There are no products(approved by the FDA) available on the markets that can make the penis longer & thicker. But there are so many false ads on the internet for linga/penis enlargement and there are so many people who blindly go by these ads. Some people have argued with me when I said 'so ans so' was fat. They say 'that's your opinion'. It is not my opinion and it is not subjective. Standing straight, if man looks down, he should be able to see his penis. If he can't see, that means he has a belly fat. It applies to females too. If a woman can't see her pubic hair, then belly fat is blocking the view. Science goes objectively.
In some Jewish and African communities, the penis is circumcised from cleanliness & some religious perspectives. Also there is a practise of Female Genital Mutilation(FGM) in some parts of Africa. But there is no scientific evidence that an uncircumcised penis causes cancer. In uncircumcised men, the glans which is the head of the penis, is covered by foreskin. The amount of foreskin varies and as long as it glides easily over the head of the penis, it is fine. All matters is, the person should be hygiene and daily clean the area under the foreskin, as it can collect fluids containing virus or bacteria, with regular soap and water. Don't use any products available on the markets and scream 'its burning, paining, swelling, scarring etc'. Reading something on the internet is different from the Physicians who actually deal with the reproductive organs of the man. So, always consult a Physician before using any product on sensitive areas like genitals. Only when the foreskin doesn't glide easily, the problem occurs. This leads to conditions called phimosis and paraphimosis. We will discuss this later with a nice example to remember these two conditions.
The shaft of the penis is covered by a hairless skin. There are three cylinders of erectile tissue inside the shaft, two running on top, smaller one running at the bottom. This smaller one contains the urethra and ends as a bulged head, called the glans. The paired cylinders on top end just behind the glans and extend into the body on both sides of the pubic bone. The main nerve, blood vessels run in between the paired cylinders on top. Nerve tendrils are spread out everywhere but mainly in the head of the penis. When these nerves are stimulated directly, a man can experience heights of sexual sensations.
The Scrotum & the Testicles: Scrotum is nothing but a skin bag that contains both the testicles and other accessories like epididymis and vas deferens. It is hairy and underneath that there is a thin layer of muscle which when contracted, the scrotum shrinks and pull the testicles closer to the body and when the muscle is relaxed, the testicles drop away from the body. The normal temperature of the testicles is 40F(1.50C) cooler than the normal body temperature which is 98.20F.
It is not necessary that the testicles have to be symmetrical. It is normal for the left testicle to hang slightly lower than the right. In this normal case, the heart is on the left and the appendix on the right. But, if the right testicle is lower than the left, then the heart is on the right and the appendix is on the left. This is called Kartagener's syndrome which is associated with lung problems and such a condition is very rare. Testes is the organ that primarily produces the male harmone Testosterone besides Adrenal glands which also produces small amounts of it. Within a testicle, there is a cluster of tubules separated by two types of cells called Sertoli and Leydig cells. It is the Leydig cells that produce testosterone and directly inject it into the bloodstream. The Sertoli cells nourishes these tubular cells which become transformed into sperms. It takes approximately 72 days for the tubular cell to be transformed into a sperm.
Just as we saw in the case of penis, same is true with testicles. Large testicles do not mean masculinity/fertility. We will see 'why this is so' when we come to 'seminal vesicles'. The size can vary from the size of an egg yolk to size of the plum. The testicles start high in the back of the abdomen near the kidney level but as the foetus grows, they slowly descend and finally in the eighth month in utero become attached to the abdominal sac. In the final month, they drop further into the scrotum by pulling peritonial lining with it which is closed at the bottom. In the normal birth, the peritoneum closes off at the top also. But there is always an opening at the top. All men are susceptible to hernia formation and there are different types of hernia. Hernia is a protrusion of an organ or part of the organ into a wall of the cavity in which it is contained. The hernia associated with testicles is called indirect inguinal hernia where the intestine is pushed into the scrotum.
The Prostate Gland: It is about the size of a walnut and 1 inch in legth and 1.5 inches in diameter. It weighs about 20g. It surrounds the urethra near the bladder sphincter. Inside the prostate are the glandular cells, muscle cells, fibrous cells intermixed with blood vessels, nerves and fat. The gland produces an important protein for fertility but has no vital function. A man can live well without a prostate. But one can not live without a heart or liver. Liver is a miracle organ and to remember the power of this organ, just think 'to live'
Since the prostate surrounds the urethra, in middle aged men, it has a tendency to grow and choke the flow of urine through the urethra. It can grow to a size of 200g without affecting the urine flow. But size alone is not an indicator for treatment. The important questions need to be asked are: Does he feel like urinating frequently day and night? Does he feel uncomfortable urinating? Does he find difficulty knowing if his bladder is emptied or not? A man can experience these symptoms with a 100g or even 30g. So, only a Physician/Urologist, after some tests will decide the course of the treatment. If it is not much of a discomfort, it can be treated with some drugs. Only when it causes real pain and discomfort, and doesn't listen to drugs, there is a choice of removing the organ.
Urethra: It is a delicate and thin walled tube about 8 inches in length. It start from the bladder and ends at the tip of the penis. It is surrounded by the sphincter muscle which keeps the urine in the bladder. Just behind the sphincter muscle is the prostrate gland. This is the site of all problems related to the prostate gland. When the prostate grows in size it can choke the urethra. The urethral walls are made of unicellular column like cells and only at the head of the penis, it becomes a multilayered walls like those in the skin. Since the passage is so delicate, any cathetars and instruments can cause scarring and blockage. This is one of the reasons, Urologists hesitate to intervene medically unless the situation warrants it. Many guys, wanting to have erection or rigidity, insert all kinds of objects(like small stick, bead,safety pin etc) into the urethra and then end up with Urologists who remove these objects! Don't mess up with the body. It has discipline and it doesn't like foreign objects. Respect the body as it is one of the marvels of nature. Bladder is the best example.
Bladder: The bladder resembles a baloon and located in the abdomen behind the pubic bone. It is defined as an uncooked egg in size & shape when empty and collapsed and as grapefruit when filled with urine. It is the kidneys that produce the urine and transport it through the ureters/tubes from the kidneys to the bladder. These ureters traverse the wall of the bladder and run under the bladder lining. This creates a flap valve that prevents back flow of urine to the kidneys. When there is urine backflow, it can cause damage to the kidneys.
As the bladder starts to fill up, its wall relaxes. No message is sent to the brain. Only when it reaches a near capacity, the bladder registers a sensation of fullness and the message is sent to the brain. As a result, the bladder muscles contract and the sphincter muscle(neck of the bladder) opens and the bladder empties the urine into the urethra. To design a 'artificial' bladder is to mimic the real bladder: when its empty, it should be like a plastic bag which can hold more fluid without changing the tension on its wall yet at the same time when its full should be like a rubber baloon. Cancer of the bladder is the most expensive to treat, also a very aggressive form of cancer which spreads to its adjacent body parts quickly and scientists have developed artificial bladder to replace the diseased bladder.
The Kidneys: We all have two kidneys which are bean shaped structure and about as large as an orange. It is not a part of reproductive system but connected to the genital organs and urologists are the surgeons who operate on them. The kidneys lie in a pad of fat and located high in the back behind abdominal lining and in front of the back muscles under the rib cage. The doctors locate the organ by tapping the back where the twelfth ribs meet the edge of the vertical back muscle. Since they are suspended free in a pad of fat, they move up and down an inch as we breathe. The kidneys are connected to the renal(pertaining to the kidneys) arteries(artery is a blood vessel carrying blood from the heart to any part of the body) which receive 25% of the blood pumped out from the heart. Renal veins(vein is a blood vessel which take the blood from any part back to the heart) take the outflow from the kidneys back to the heart.
Epididymis: It is like a comma shaped structure that drapes over the back side of each testicle. It is 1 inch long and 0.5 inch wide. It has a head on top, body in the middle and a tail. When it is cut open, there is a cluster of tubules and if these tubules are dissected out, they form a continuous tube. Sperms are produced in the testicles but in epididymis they get matured and aquire the ability to swim. The sperms recovered from the head can not swim and hence are unlikely to create pregnancy while those recovered from the tail part are much more fertile.
Vas Deferens: It is a tube that extends from each epididymis, that conducts sperms towards the seminal vesicles. The vas is thick like a wire and 1 foot long. The vas is mainly muscle and making it a hard cord that can be felt through the scrotal skin. When it is cut open, it is hard to find the inside canal(that conducts sperm) as it is so small. If a man is no longer interested in fathering a child, he can go for vasectomy, which is the removal of vas deferens. Even if he has 'unprotected' sex, he doesn't have to worry about making his woman pregnant as there would not be any sperms in the ejaculation as the vas/tube that conducts sperms has been removed! Or sometimes, instead of removing the entire vas deferens, they disconnect the tube end. Later, if the man decides to have a baby, it can be reattached. Few men are congentially bilateral vas deferens absent. The male hormones testosterone and DHT(dihydrotestosterone) are responsible for male characteristic growths like facial hair and vas deferens tubes. Vas deferens ducts don't develop properly in 1 to 2 % of men and hence will not be able to father children as sperms can not be transported out of the testes to the ejaculate.
Seminal Vesicles: These are irregular structures each roughly 2 inches, lying above the prostate and connected to the vas in the Y shape so that a single ejaculatory duct drains both vas and the seminal vesicles into the urethra which is also a passage for urine. When a man has erection, the bladder's sphincter muscle gets closed so that urine doesn't get mixed with semen. The seminal vesicles produce a gelatinous substance that becomes a part of the ejaculate. They also produce fructose, a simple sugar found in fruits. In infertility testing, if the ejaculate contains no fructose, then the man was born without seminal vesicles and he is 'irrevocably' infertile. Meaning he can't father a baby and the only option is to go for adoption.
The actual reproductive organs/structures are testicles, penis, prostate and seminal vesicles. We had to see other organs as they are all related to these genital organs.