27.- THE MALE REPRODUCTIVE SYSTEM

27.- THE MALE REPRODUCTIVE SYSTEM

 The human male reproductive system (or male genital system) consists of a number of sex organs that are a part of the human reproductive process. In this type of reproductive system, these sex organs are located outside the body, around the pelvic region.
The main male sex organs are the penis and the testes which produce semen and sperm, which as part of sexual intercourse fertilize an ovum in female's body and the fertilized ovum (zygote) gradually develops into a fetus, which is later born as a child.

External genital organs

The penis is the male copulatory organ. It has a long shaft and enlarged bulbous-shaped tip called the glans penis, which supports the foreskin. When the male becomes sexually aroused, the penis becomes erect and ready for sexual activity. Erection occurs because

sinuses within the erectile tissue of the penis become filled with blood. The arteries of the penis are dilated while the veins are passively compressed so that blood flows into the erectile cartilage under pressure.
The scrotum is a pouch-like structure that hangs behind the penis. It holds and protects the testes. It also contains numerous nerves and blood vessels. During times of lower temperatures, the Cremaster muscle contracts and pulls the scrotum closer to the body, while the Dartos muscle gives it a wrinkled appearance; when the temperature increases, the Cremaster and Dartos muscles relaxes to bring down the scrotum away from the body and remove the wrinkles respectively. The scrotum remains connected with the abdomen or pelvic cavity by the inguinal canal. (The spermatic cord, formed from spermatic artery, vein and nerve bound together with connective tissue passes into the testis through inguinal canal.)

Internal genital organs

The epididymis is a whitish mass of tightly coiled tubes cupped against the testicles. It acts

as a maturation and storage place for sperm before they pass into the vas deferens, tubes that carry sperm to the ampullary gland and prostatic ducts.
The vas deferens, also known as the sperm duct, is a thin tube approximately 43.2 centimetres long that starts from the epididymis to the pelvic cavity.
Three accessory glands provide fluids that lubricate the duct system and nourish the sperm cells. They are the seminal vesicles, the prostate gland, and the bulbourethral glands (Cowper glands).
Seminal vesicles are sac-like structures attached to the vas deferens at one side of the bladder. They produce a sticky, yellowish fluid that contains fructose. This fluid provides sperm cells energy and aids in their motility. 70% of the semen is its secretion.
The prostate gland surrounds the ejaculatory ducts at the base of the urethra, just below the bladder. The prostate gland is responsible for the production of semen, a liquid mixture of sperm cells, prostate fluid and seminal fluid.This gland is also responsible for making the semen milky by mixing calcium to the semen coming from seminal vesicle(semen coming from seminal vesicle is transparent in colour),this process is called profibrinolysin .28 to 29% semen comprises its secretion.
The bulbourethral glands, also called Cowper glands, are two small glands located on the sides of the urethra just below the prostate gland. These glands produce a clear, slippery fluid that empties directly into the urethra. It produces substances related to nourishment of spermatozoa.

PHYSICAL EXAMINATION

A physical examination, medical examination, or clinical examination (more popularly known as a check-up or medical) is the process by which a doctor investigates the body of a patient for signs of disease. It generally follows the taking of the medical history — an account of the symptoms as experienced by the patient. Together with the medical history, the physical

examination aids in determining the correct diagnosis and devising the treatment plan. This data then becomes part of the medical record.

GYNECOMASTIA

Gynecomastia or Gynaecomastia, ˌɡaɪnɨkɵˈmæstiə/, is the abnormal development of large mammary glands in males resulting in breast enlargement. The term comes from the Greek γυνή gyné (stem gynaik-) meaning "woman" and μαστός mastós meaning "breast." The condition can occur physiologically in neonates (due to female hormones from the mother), in adolescence, and in the elderly (Both in adolescence and elderly it is an abnormal condition associated with disease or metabolic disorders). In adolescent boys the condition is often a source of distress, but for the large majority of boys whose pubescent gynecomastia is not due to obesity, the breast development shrinks or disappears within a couple of years

SCROTAL DISORDER

The three most common disorders that affect the scrotum, the sac beneath the penis that holds the testicles, include:

• Hydroceles, the collection of fluid within a section of the scrotum called the tunica vaginalis;
• Varicoceles, which is an enlarged group of veins above the testicles and along the vas deferens, a blood vessel-rich cord that connects the epididymis to the prostate gland; and

Spermatoceles, which are sperm-filled cysts at the head of the epididymis, a coil of tubes behind the testicles where sperm are stored

Symptoms
Hydrocele. When symptoms occur they may include a bulky, achy feeling in the scrotum.

Varicoceles. The most common symptom for varicoceles is a heavy, dragging, aching feeling in the scrotum, which often increases throughout the day.

Spermatoceles. There are usually no symptoms associated with spermatoceles. In some cases, they may grow large enough to create chronic pain or cause tight fitting clothes to be uncomfortable.

PROSTATE DISORDERS

The prostate is a gland located at the base of a man’s bladder, behind the pubic bone and in front of the rectum. This gland, which is roughly the size and shape of a small crab apple, weighs only about an ounce in young men. It surrounds the urethra, the tube that carries

urine away from the bladder and transports semen during ejaculation. A good way to envision the prostate is as an apple with the core removed, with the urethra passing through the middle.

The prostate’s primary function is to produce prostatic fluid, a component of semen. Also, during ejaculation, smooth muscles in the prostate contract to help propel semen through the urethra. Technically the prostate is not part of the urinary system. But because of its location and relationship to the urethra, the prostate can (and often does) affect urinary function.

Prostate cancer: After skin cancer, prostate cancer is the second most common cancer in American men and is second only to lung cancer as a cause of cancer deaths. In 2009, an estimated 192,000 men were diagnosed with prostate cancer, and about 27,000 died of the disease.

The good news is that reliable diagnostic tests and numerous treatment options are available, and death rates from prostate cancer are on the decline. Nearly 100 percent of men are still alive five years after a prostate cancer diagnosis, about 93 percent are alive 10 years after diagnosis, and approximately 79 percent are alive 15 years after diagnosis.

Although the symptoms of prostate cancer are similar to those of benign prostatic hyperplasia (BPH), the conditions are not related. Having BPH neither increases nor decreases.

CANCER

Cancer, known medically as a malignant neoplasm, is a broad group of various diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming

malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the body through the lymphatic system or bloodstream. Not all tumors are cancerous. Benign tumors do not grow uncontrollably, do not invade neighboring tissues, and do not spread throughout the body. There are over 200 different known cancers that afflict humans.
Determining what causes cancer is complex. Many things are known to increase the risk of cancer, including tobacco use, certain infections, radiation, lack of physical activity, obesity, and environmental pollutants. These can directly damage genes or combine with existing genetic faults within cells to cause the disease. Approximately five to ten percent of cancers are entirely hereditary.
Cancer can be detected in a number of ways, including the presence of certain signs and symptoms, screening tests, or medical imaging. Once a possible cancer is detected it is diagnosed by microscopic examination of a tissue sample. Cancer is usually treated with chemotherapy, radiation therapy and surgery. The chances of surviving the disease vary greatly by the type and location of the cancer and the extent of disease at the start of treatment. While cancer can affect people of all ages, and a few types of cancer are more common in children, the risk of developing cancer generally increases with age. In 2007, cancer caused about 13% of all human deaths worldwide (7.9 million). Rates are rising as more people live to an old age and as mass lifestyle changes occur in the developing world