Male reproductive system

What is the male reproductive system?

The male reproductive system is the set of organs and structures of the human body that is related to the sexual reproductive processes of man. It is made up of different organs such as the penis and testicles.

Although men and women are very similar in many physical and physiological aspects, an important part of the differences that we observe between them has to do with the particular characteristics of each of their reproductive organs, which in men are determined by the presence of genes belonging to the Y sex chromosome.

These differences are precisely those that make it possible for men and women to establish sexual relationships that result in the formation, development and birth of new human beings, which contributes to the continuity of our species.

The woman has special reproductive structures to support the development of an embryo after fertilization, and she is the one who provides all the nutrients and the environment conducive to its growth. As for the man, his participation is fundamental, because without sperm there can be no fertilization.

Sexual reproduction is only possible if a man and a woman come together to bring their gametes closer together, which are the sex cells from whose fusion a zygote will result, which will later become an embryo, then a fetus and finally a baby.

Female gametes are known as ovules and are large immobile cells, meanwhile male gametes are known as spermatozoa and are flagellate cells, much smaller than ovules, with the ability to move by "swimming".

Both eggs and sperm contain half of the chromosomal load of the individual that gave rise to them, and that is why when they fuse with each other during fertilization, a new cell is formed in which the chromosome content that characterizes it has been restored. to human beings.

Functions of the male reproductive system

The male reproductive system is not only essential for reproduction, but also participates in the production of hormones related to the control of different physical characteristics of man.

From the reproductive point of view, this set of organs works in the production of spermatozoa (male sex cells), in their transport and release within the female reproductive tract, specifically in the vagina, which is the channel that connects with the uterus.

This occurs when a man and a woman have sexual intercourse and the man inserts his penis into the woman's vagina to release the fluid that contains sperm cells, capable of swimming towards the eggs released into the fallopian tubes during ovulation..

Production of sex hormones

The male reproductive system has a pair of very important glands -the testicles- on whom the production of testosterone, the main male sex hormone, depends.

Testosterone can also be produced in small amounts by the adrenal gland, in both men and women, but it does not compare to the amount produced by the testes. This hormone has multiple functions in the human body, including:

• Control of libido or sexual appetite.
• The development of bone mass (of the bones).
• The distribution of body fat.
• Modifying the tone of voice.
• The growth of facial and body hair.
• The strength and size of the muscles.
• The production of red blood cells and sperm.

Parts of the male reproductive system

Just as is true for the female reproductive system, the male reproductive system consists of a series of internal organs and external organs, collectively known as the genitalia. These organs are the following:

• The testiclesThey are a pair of egg-shaped glands found in the scrotum, on the outside of the pelvis, and very close to the penis. Inside are the tissues necessary for the production of sex cells and are also responsible for the production of the male sex hormone called testosterone.
• Scrotum: the scrotum is a "loose skin sac" that hangs outside the pelvis, under the penis and is responsible for holding the testicles in place.
• The epididymis: It is a highly coiled tube that is in the inner back part of the testicles. Immature sperm produced in the testes must travel through this duct and, as this occurs, they mature and acquire the ability to swim..
• Different conductor: it is another duct attached to the epididymis; has thicker walls and is responsible for the conduction of sperm from the epididymis to the prostate and urethra (a channel also associated with the urinary system for the expulsion of urine out of the body).
• The prostate gland: It is a walnut-shaped gland that is found in the medial inner region of the male pelvis and is crossed by the urethra. Its job is to produce secretions or substances that nourish sperm cells..
• Urethra: it is the tube associated with both the urinary system (specifically the urinary bladder) and the male reproductive system; through this urine and sperm are expelled. Opens outward at the tip of the penis.
• Penis: it is one of the main male genitalia and perhaps the most obvious; It is an organ made up of three columns of spongy erectile tissue, capable of filling with blood and increasing its size during erection. It has two functions, since it is through which men can urinate and copulate.

Functioning

Sperm production in a human first occurs during puberty, analogously to ovulation, which first occurs during female puberty.

This process is known as spermatogenesis and occurs in the testes, specifically in ducts known as seminiferous tubules. At the beginning of puberty, it is normal for the scrotum and testicles to increase in size, which later happens with the penis, prostate and other associated organs.

Spermatogenesis is a process that is highly controlled by the nervous system and the endocrine system, which means that it depends on the action of different electrical and hormonal signals..

An adult (or sexually mature) human produces and stores millions of sperm in the testes daily. Sperm are small flagellate cells that are very similar to a tadpole, which progressively mature as they are produced..

If a sexually mature man and woman have intercourse during the ovulation phase of a woman's menstrual cycle, fertilization can occur.

Sexual arousal is generally one of the events leading up to intercourse and, in men, it is necessary for several reasons:

• The penis is hardened by increased blood flow, which makes it easier to insert into the vagina.
• The prostate produces seminal fluid that mixes with sperm to nourish them and provide a vehicle for their movement..
• The muscles around the genitals contract, forcing semen to travel along the internal duct system, eventually reaching the urethra during ejaculation..

When a man ejaculates inside a woman's vagina, he releases about 500 million sperm that travel through the uterus to the fallopian tubes, where a mature egg is found..

Only one sperm can penetrate the ovum, losing its flagellum at the same time as the cell membranes of the ovum and the sperm fuse and the nucleus of the sperm is deposited inside the ovum, with whose nucleus it will be able to fuse; this is the process known as fertilization or fertilization.

Diseases

Like any other organ system of the human body, the male reproductive system can suffer different conditions or pathologies that can lead to its malfunction, discomfort, etc., among these are:

• Impotence, having to do with the inability to obtain an erection suitable for intercourse.
• Loss of libido or sex drive, probably due to hormonal deficit.
• Cancer: in the testicles or in the prostate
• Difficulty urinating, because the urethra works both in the urinary system and in the reproductive system. It can occur for different reasons, but a very common one is inflammation of the prostate.
• Hydrocele: formation of a fluid-filled sac around the testicles; looks like swelling on the sides of the scrotum and can be bothersome, so it is usually surgically removed.
• Varicocele: exaggerated dilation and twisting of the veins supplying the testicles. They are similar to hemorrhoids, but occur in the scrotum and look like a swelling or a "bag of worms"; may be related to male sterility.
• They can also occur viral infections (like herpes) or bacterial in the external or internal tissues of the genitals, either due to poor hygiene or sexual transmission.

Themes of interest

Human fertilization.

Female reproductive system.

References

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