Reproductive System: Facts, Functions and Diseases

The reproductive system is a collection of organs that work together for the purpose of producing a new life. Scientists argue that the reproductive system is among the most important systems in the entire body. Without the ability to reproduce, a species dies.

The major organs of the reproductive system include the external genitalia and internal organs, including gonads that produce gamete, which is a cell that fuses with another cell during conception in organisms that reproduce sexually. Substances such as fluids, hormones, and pheromones are also important to the effective functioning of the reproductive system.

The male reproductive system consists of two major parts: the testes, where sperm are produced, and the penis. In humans, both of these organs are outside the abdominal cavity. Having the testes outside the abdomen facilitates temperature regulation of the sperm, which require specific temperatures to survive. If the testicles remain too close to the body, the higher temperature will likely harm the spermatozoa, making conception more difficult or impossible. The testes are carried in an external pouch known as the scrotum, where they normally remain slightly cooler than body temperature to facilitate sperm production.

The two major parts of the female reproductive system are the vagina and uterus — which act as the receptacle for semen — and the ovaries, which produce the female's ova. The vagina is attached to the uterus through the cervix, while the Fallopian tubes connect the uterus to the ovaries. In response to hormonal changes, one ovum, or egg — or more in the case of multiple births — is released and sent down the Fallopian tube during ovulation. If not fertilized, this egg is eliminated as a result of menstruation.

The fertilization of the ovum with the sperm occurs only at the ampullary-isthimic junction, which is why intercourse does not always result in pregnancy.

At the time of conception, the ovum meets with spermatozoon, where a sperm may penetrate and merge with the egg, resulting in fertilization. While the fertilization usually occurs in the oviducts, it can also happen in the uterus itself. The egg then becomes implanted in the lining of the uterus, where it begins the processes of embryogenesis and morphogenesis. When the fetus is mature enough to survive outside of the womb, the cervix dilates and contractions of the uterus propel it through the birth canal.

Diseases of the reproductive system

There are many parts of the male and female reproductive systems that can be affected by cancer. In females, cancer can attack the uterus, ovaries, breast and cervix, among other organs. Males can develop prostate, testicular and penile cancer.

Both genders can develop sexually transmitted diseases, including genital herpes, gonorrhea and syphilis. HIV/AIDS, a disease of the immune system, is not exclusively transmitted through sexual contact; sexual activity is one of the ways that the HIV virus is spread.

While genital human papillomavirus (HPV) is commonly associated with females, it is the mostly commonly sexually transmitted infection and most sexually active people in the United States, male and female, will have HPV at some time in their lives. In most people it causes no problems, but in women it can result in cervical cancer and genital warts and in men it can cause penile and anal cancer and genital warts.

For females, one of the more common disorders of the reproductive system is a vaginal yeast infection, which is caused by a yeast fungus in the vagina.

Endometriosis is a condition involving colonization of the abdominal/pelvic cavity with islands of endometrial tissue. If endometrial tissue flushes up the uterine tube during menstruation and spills into the abdomen, the clots of endometrial tissue can attach to abdominal organs such as the bladder, rectum, intestinal loops and then cycle along with the uterus in response to monthly changes in ovarian hormones.

Pelvic inflammatory disease is a condition where bacteria can make their way up the vagina, through the uterus, and traverse the uterine tubes which open into the abdominal cavity.

In women with a prolapsed uterus, the ligaments that hold the uterus in proper position so that it does not prolapse, or herniate, into the vagina, have failed.

Infertility is defined as a couple's inability to conceive after one year of regular intercourse.

In males, infertility is a condition in they produce no sperm cells (azoospermia), too few sperm cells (oligospermia), or if their sperm cells are abnormal or die before they can reach the egg. Chronic problems with ejaculation (sperm released at orgasm) also contribute to male infertility. In rare cases, infertility in men is caused by an inherited condition, such as cystic fibrosis or chromosomal abnormalities.

Men can also experience epididymitis, which is an inflammation of the epididymis, the tube that lies on and around each testicle and plays a role in the transportation, storage, and maturation of sperm cells.

Another condition of the male reproductive system is hypogonadism, which occurs when the testicles do not produce enough testosterone.

In women, infertility is defined as a disorder of the reproductive system that hinders the body's ability to ovulate, conceive, or carry an infant to term.

Reproductive conditions are treated by a variety of specialists. In women, many issues are treated by obstetricians/gynecologists and for males urologists handle many disorders of their reproductive systems. There are also infertility experts that treat couples who are unable to conceive and endocrinologists who treat hormonal disorders.

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Facts, Functions & Diseases:

• Circulatory System
• Digestive System
• Endocrine System
• Immune System
• Integumentary System (Skin)
• Lymphatic System
• Muscular System
• Nervous System
• Respiratory System
• Skeletal System
• Urinary System