Post Date December, 03 2023
How miraculous is a man's testicles that can produce so many sperm in just one day??
Everyone knows that human pregnancy is about sperm and eggs, and the combination of the two can produce the next generation. In fact, a long time ago, male sexual health editors thought that why there are so many sperm and only one egg? In fact, if there are also many eggs, it would really be anti human. Once a woman becomes pregnant, it would be a fatal disaster. Hehe, the editor is just having an affair, don't hit me. Today, the editor wants to discuss with everyone, what kind of organism is sperm???
If you have the opportunity to look at sperm under a microscope, you will definitely exclaim. Densely packed sperm, resembling tadpoles, with a small head (6 microns long) and a long tail (60 microns). It is this long tail that enables sperm to vigorously swim forward, searching for eggs and combining with them.
However, sperm activity is quite fast. If you have the opportunity to see sperm piercing into an egg, hundreds of sperm sticking their heads together to a much larger egg (150 microns), their tails swinging outwards, struggling to drill in, you will be even more amazed! Due to the movement of sperm, the zygote and other sperm around it rotate rapidly and continuously, as if they are dancing the dance of life.
After watching these exciting scenes, you will definitely ask, how do sperm come into being and why are the testicles so small that they can produce hundreds of millions of sperm every day? To answer this question, one must start with the anatomical morphology and tissue structure of the testicles.
The testis is the male gonad, where sperm is produced and sex hormones are secreted. From the appearance, the testicles are one on each side, slightly flattened in an oval shape, located inside the scrotum. In the early stages of the fetus, they descend into the scrotum in the abdominal cavity before birth. Adult testicles, approximately 4 centimeters long, 3 centimeters wide, and weighing approximately 20 grams.
In clinical practice, testicular volume is commonly used to represent its size (15-20 milliliters). The testicles of newborn babies are relatively large and have shrunk approximately 1-2 months after birth. Before sexual maturity, the testes are basically in a static state, and develop rapidly after puberty. Around the age of 50, it gradually shrinks and becomes smaller.
The testicles look like the color of fresh shrimp, with a white to red hue, and a trace of blood vessels can be seen on top. The outer surface of the testicles is covered with a slightly thick and strong white film, which plays an important protective role in the testicular parenchyma. If the tunica albuginea is cut open, the testicular tissue will become soft and paralyzed into a pile, unable to maintain its original form. The outer layer of the tunica albuginea is the tunica vaginalis of the testes, which is the component of the peritoneum brought down during the descent of the testes during the embryonic period.
There is a small amount of liquid between the tunica albuginea and the tunica vaginalis, which maintains lubrication and allows the testicles to have some activity. The white membrane extends inward to form a radial mediastinum, dividing each testicle into approximately 200-300 intervals from the inside. We refer to them as "testicular lobules," and each lobule is surrounded by curved microtubules called "seminiferous tubules.
In adults, its diameter ranges from 150 to 250 microns, with varying lengths, mostly between 30 to 70 centimeters, and up to 150 centimeters in length. There are approximately 300-1000 such small tubes in each testicle, and if they were connected together, they would be approximately 200-300 meters long. All the convoluted seminiferous tubules converge at their terminals, forming the testicular network. One end of the net is divided into about ten output tubules, which pass through the white membrane outside the testicles and eventually converge into the epididymis. Sperm is constantly produced in the convoluted seminiferous tubules. The small testicular structure is so delicate and complex that it has a large area for spermatogenesis, which is why the testicles can produce so many sperm every day.
There are two types of cells in the epithelium of seminiferous tubules: one is the spermatid cells at different stages of development, and the other is the supporting cells. The spermatid are embedded in the irregular pits on the surface of the supporting cells. The most immature spermatid are near the basement membrane, while the mature spermatid are near the central lumen. With the continuous development of spermatid, they constantly move from the base to the lumen. A spermatogonium can form 256 sperm cells with only half of the chromosomes after multiple mitosis and two maturation divisions (meiosis), of which 50% contain X chromosomes and 50% contain Y chromosome.
The shape of spermatogonium and spermatocyte is round, and there is no tail. The tail gradually appears when the sperm cells arrive. Sperm cells undergo a series of changes and eventually mature, forming sperm like tadpoles that are discharged into the seminiferous tubules. Sertoli cells have many functions, can secrete a variety of active substances, and play a role in regulating and assisting the differentiation, maturation, sperm discharge, and phagocytosis of degenerated spermatid. Sperm is produced every moment in the testicles of adults. It has been estimated that every gram of testicular tissue in adults can produce 300-600 sperm per second, and bilateral testicles can produce hundreds of millions of sperm per day. This is also one of the reasons why male contraceptive methods that control sperm production are much more difficult than inhibiting female ovulation.
