The organs of the male reproductive system are specialized for the following functions:
• To produce, keep, and release sperm cells (the male reproductive cell) and semen (the fluid which acts as a protective agent to keep the sperm alive)
• To ejaculate or discharge semen containing sperm
• To secrete and produce the male sex hormones
• To produce, keep healthy, and transmit the male reproductive cells and transport it within a protective fluid called semen
• To transmit sperm cells within the female reproductive system
The anatomy of male reproductive system has internal and external structures or form.
What are the external reproductive structures?
The external structure of the male reproductive system is mostly found outside the body of male humans. These are the penis, the scrotum and the testicles.
Penis — This is the organ used by male for copulation or sexual intercourse. It is composed of three parts, namely, the root of the penis, which is attached to the abdominal walls; the body of the penis, or sometimes called shaft, which is composed of fleshy structure which becomes hard when filled with blood during erection; and the glans, or the cone-shaped structure attached to the end of the penis. The glans is also called the head of the penis. This is covered with foreskin—a layer of skin which is sometimes removed during circumcision procedure. Found at the tip of the glans of the penis is a tiny opening of the urethra—the tube which functions as a transport system for semen and urine. Due to the large concentration of nerve endings located at the glans of the penis, this provides for the added sensitivity of the said structure.
The body of the penis is somewhat shaped in a cylindrical manner. It has three internal chambers. The composition of these internal chambers is of special and sponge-like tissues necessary during erection. Erection occurs when, the male is excited or aroused sexually, the erectile tissues becomes filled with blood thereby making it hard and erect, which makes it possible for penetration of the vaginal during sexual intercourse. The outer skin covering the erectile tissues are loose, flexible and elastic thus making it possible to adjust to the changes in shape and size during erection.
Semen - this is the fluid which carries sperm during ejaculation. Ejaculation occurs then the man reaches orgasm or the peak of sexual activity or sometimes refered to as climax. During erection, urine cannot flow because it is blocked by the urethra and only the semen is allowed to flow during orgasm or ejaculation.
Scrotum — This is the loose and pouch-like sac of skin which hangs posterior to the penis. Inside the scrotum are the testicles, also called testes, bunch of nerve endings, and blood vessels. The function of the scrotum is to serve as climate control system for the testes which is sensitive to extreme temperatures as this could affect the life of the sperm produced therein. The main reason why the testes hang outside the body is to keep the sperm in a temperature which is lower than that of the human body to keep them alive and healthy. When extreme cold temperature is detected, the scrotum contract which draws the testes closer to the body to provide the necessary warmth for the sperm, and upon the other hand, when a hot temperature is detected in the body, the scrotum relaxes to keep the testes away from the body to provide cold temperature.
Testicles (testes) — These are the oval-shaped organs found inside the scrotum. They are about the size of large olives and are secured at either end by what is termed as the spermatic cord. Normally, men have two testes. The primary function of these organs is to produce testosterone, which is the primary male sex hormone, and produce sperm cells. Inside the testes are tubes masses which are coiled or bundled together. They are called as the seminiferous tubules. These tubules function by producing sperm cells in a process called spermatogenesis.
Epididymis — This is the long, coiled tube-like structure which is located on the posterior of each testicle. Its primary function is to transport and store sperm cells which are produced inside the testes. Another function of the epididymis is to nurture the sperm until it matures. This is because the sperm produced in the testes are basically immature and not capable of fertilization. During the arousal stage of sexual activity, the contractions of the genitals force the sperm which are contained in the fluid-like semen into the vas deferens.
What are the internal reproductive organs?
After the discussion of the external internal organs of the male reproductive system, what then are the internal organs of the male reproductive system? These internal organs are also called accessory organs. They include the following:
Vas deferens — This is a long and muscular tube which connects the epididymis to the pelvic cavity which is at the posterior of the bladder. The main function of the vas deferens is to carry mature sperm cells via the urethra in anticipation for the ejaculation process.
Ejaculatory ducts — These organs are the outcome of the fusion of the vas deferens and the seminal vesicles. These ducts empty into the urethra.
Urethra — This is the tube-like structure which is the passage of the urine from the bladder to be discharged outside the body. In male reproductive system, it has an additional function of ejaculating semen during climax or orgasm. During erection, the flow of urine is hindered or blocked from the urethra, thus allowing only semen to be expelled outside.
Seminal vesicles — These are the sac-like pouches which are attached to the vas deferens located proximal to the base of the bladder. The main function of the seminal vesicles is to produce fructose, a fluid rich in sugar which is needed to provide the sperm a source of energy and help in adding motility or the ability to move or propel once it is lodged inside the female reproductive tract during copulation. The fluid produced makes up the most concentrate of the male’s ejacule.
Prostate gland — This gland is the walnut-sized structure which is inferior to the urinary bladder and anterior of the rectum. The main function of this gland is to provide additional fluid to the ejaculate, provide nourishment to the sperm. The center of the prostate gland is where the urethra, carrying the ejaculate during orgasm, runs through.
Bulbourethral glands — The bulbourethral glands, or Cowper’s glands are the structures just lateral the urethra and inferior to the prostate gland. The main function of these glands is to produce a clear, slippery fluid that passes directly through the urethra. The said fluid acts as a lubricant and neutralizer to the acidity which may be produced by droplets or residues of urine passing through the urethra.
How does the male reproductive system function?
The male reproductive system depends on hormones. Hormones are the chemicals that regulate or stimulate body functions. The main hormones in the proper functioning of the male reproductive system are the follicle-stimulating hormone (FSH), luteinizing hormone (LH), and the testosterone.
The follicle-stimulating hormone (FSH) and the luteinizing hormone (LH) are produced by the brain, specifically by its pituitary gland which is located at the base of the brain. FSH is important for the production of the sperm cells or the process called spermatogenesis. The LH is responsible of the stimulation of the production of the testosterone. This is necessary to continue the process of spermatogenesis. Testosterone, upon the other hand, is necessary in the development of male characteristics. Some examples of male characteristics are muscle mass, strength, fat distribution, bone mass, and sex drive.