The male reproductive system is responsible for many different functions; among them, the main function would be the production, maintenance, and transport of male reproductive cells or the ‘sperm’. However, it does not stop at just producing ‘sperms’ as it contributes to the development of male characteristics of a person by secreting the hormone ‘testosterone’ and by providing means to expel ‘sperm’ into the female reproductive system at the time of the intercourse.
In males, the reproductive system consists of several organs and some of them reside outside the body in order to maintain the optimum temperature for ‘sperm’ production, which should be slightly cooler than the usual body temperature. At the same time, some of the organs perform a dual function of transporting urine as well as ‘semen’, which contains the male reproductive cells. However, there are mechanisms in place to prevent urine from exiting from the bladder at the time of expelling ejaculatory fluids (semen) which will make sure, urine and semen are never mixed at the time of exit.
Organs of the male reproductive system:
As mentioned before, some of the organs belonging to the male reproductive system reside outside the body and these include the penis and the scrotum. The scrotum contains the paired testes, a rich vasculature, and a nerve supply. Other organs including the epididymis, vas deference, ejaculatory ducts, seminal vesicles, prostate, bulbourethral glands, and the urethra reside within the pelvis. All of these organs are closely related.
Structure and function of each organ:
The penis is the organ which facilitates intercourse and expulsion of semen into the female reproductive system during ejaculation. It consists of a root, a shaft, and a glans at the tip of the penis. The urethra, which carries both urine and semen, opens up at the tip of the penis, which is usually covered by a fold of skin known as the ‘foreskin’. When a male is sexually aroused, the penis will become erect and stiff. The reason for this phenomenon is the filling up of its spaces inside the penile shaft with blood at the time of sexual arousal.
Most males will have two testicles inside their scrotum and each testicle is suspended inside the scrotum through a spermatic cord. It provides a dual function of producing sperm as well as secreting the hormone ‘testosterone’. The seminiferous tubules located within the testes would be the production facility for sperm and at the time they exist the testes, the sperm are not mature enough to be effective reproductive cells.
These lengthy tubular structures are located behind the testes and will store immature sperm released from the testes until they reach maturity. At the time of sexual arousal, these sperm will be pushed into the next portion of the passage, which is the vas deference.
Vas deference –
The sperm pushed into the vas deference will travel through this muscular tube into the upper portion of the urethra.
Seminal vesicles –
These are pouch-like structures, which attach themselves to the vas deference just before it opens up into the urethra. It is located just behind the bladder and produces a sugar rich fluid which ultimately contributes to a significant volume of the seminal fluid. The sugar rich medium will provide the sperm's energy for motility, especially when they land on the female reproductive system.
Ejaculatory ducts –
This is the common passage for both the vas deference and the seminal vesicles. It empties into the urethra.
A pear-shaped organ, the prostate produces additional secretions to nourish the sperm. It is located just underneath the bladder and the upper portion of the urethra runs through the prostate soon after it emerges from the bladder.
Bulbourethral glands –
These glands are located just below the prostate on either side of the urethra. The function of these glands has been recognized as producing a secretion, which will lubricate the urethra and dissipates acidity which may harm the integrity of the sperm travelling through the urethra after the passage of urine.
As described in various sections, the urethra facilitates the final transport of the ejaculatory fluid through the penis and it extends from the base of the bladder to the tip of the penis. A mechanism at its origin prevents the urine in the bladder from entering the urethra at the time of ejaculation.