The Amazing Truth About Sperm “Tadpoles” I am Mr. Sperm, the reproductive cell of male organisms. I am Mr. Sperm. I am the reproductive cell of male organisms. Animals and seed plants produce me, Mr. Sperm. In humans, I am a mature male germ cell whose main function is forward movement and fertilization of the egg, whereby the genetic material is delivered to the egg. My shape is quite different from that of a typical cell. Sperm from various animals can be categorized as typical and atypical. Typical ones are generally tadpole-shaped, with a sub-cylindrical head (which varies from animal to animal) and an elongated, flagellar-like tail. Sperm is the smallest cell in the body. Mature human sperm is shaped like a tadpole, about 60 micrometers long, and consists of a head containing the genetic material of the parent and a tail with motor function. My head is oval on the front and pear-shaped on the side, containing a highly concentrated nucleus with very dense chromatin, and the first 2/3 of the nucleus is covered by a cap-shaped acrosome. My tail is divided into 3 parts: the center, the main section and the end section. The main structure is the center contains an axoneme (similar to a flagellum) that runs through the entire tail, and the middle section contains helically arranged mitochondria. Birthplace, occurrence and maturation of sperm In higher organisms, my birthplace is the testes. The testes are the male gonads, and the main function of the testes, in addition to secreting the essential male sex hormones, is to produce me – Mr. Sperm. An adult man can produce between 700 and 150 million me’s per day. In the human embryo, primordial germ cells are recognizable around day 24 of development. At this time they appear in the yolk sac. The cells undergo mitosis and travel to the primordial gonads located in the germinal ridge in the 4th to 5th week. The primordial germ cells undergo cell division and rapidly increase in number, up to 1300 primordial germ cells by day 42, which later become either oogonia or spermatogonia present in the undifferentiated gonads. In the early stages of testicular differentiation, primordial germ cells are evenly distributed in the seminiferous tubules. They remain quiescent throughout early childhood, but during early pubertal development, spermatogonia begin to proliferate and undergo mitosis to become primary spermatocytes, waiting until pubertal development to begin meiosis. I, Mr. Sperm, am formed from the primary spermatogonia through meiosis to form four spermatocytes in the convoluted ducts (seminiferous tubules) of the testis. The sperm cells undergo a process of metamorphosis and development that excludes most of the cytoplasm and undergoes a series of internal changes to become Mr. I-Sperm. I, Mr. Sperm, take about 10 weeks (64-72 days) to reach maturity in the seminiferous tubules. The mature me is stored in the epididymis, where it remains for about 19-25 more days to mature further, at which point the sperm becomes mobile and capable of fertilization. So, the entire maturation process of sperm takes about 90 days. This is why the use of medication to treat azoospermia or oligozoospermia or weak or abnormal spermatozoa should last for at least 3 months. So do not be in a hurry, just take a few days of medication, a look at my number and activity rate of no change, and immediately downhearted, change another drug, in the end, a variety of drugs tasted, but all the results. The testicles must be at a temperature 3-5 degrees below body temperature to produce a healthy amount of me. So, when the temperature of my house scrotum rises, I die of heat (necrospermia) or become old and weak (weak or abnormal spermatids), resulting in infertility. Throughout adult life, the testes provide sperm at a constant rate. Evidence of normal spermatogenesis has been seen in men in their 80s and 90s. This efficient and continuous process provides incredible fertility. It takes about 3 months for me to mature to ejaculate, and the average number of ejaculations in a man’s lifetime is 7,200, including 2,000 masturbatory ejaculations. The average volume of ejaculate in a man’s lifetime is 53 liters, and Mr. Sperm can move up to 28 mph during ejaculation, and the time it takes for my Mr. Sperm to swim to Ms. Egg is 2.5 seconds. Sperm transportation, fertilization A man has about 3 million spermatozoa at the tip of his erect genitals. A normal sexually mature man can discharge tens of millions or even up to about 200 million sperm in a single ejaculation. Semen is ejaculated into the vagina, and most of the semen is alkaline, which helps the journey of sperm. A woman’s vaginal environment is acidic and sperm swim out of the seminal plasma, most sperm lose their vigor in the vagina and die. Sperm live no more than eight hours in the vagina, and just a small percentage of sperm get out and move on. By the time the sperm scrambles upstream to reach the uterine cavity, there are only 1-5% as many as there were at the time of ejaculation. Poor quality sperm are slower, do not reach the uterine cavity as quickly, and lose their vitality. After passing through all the hurdles, there are very few Mr. Sperm left that can finally reach the fertilization site in the fallopian tube. As long as I enter the fallopian tube, I have a strong ability to fertilize, and my ability to fertilize can be maintained in the female reproductive tract for about 1 day. The only thing that is stored in the mucosal crypts of the cervix is that I can live up to 2-6 days. A recent study published on the website of the British journal Nature shows that sperm from the same source will be connected to each other like train carriages, and will work together to swim forward, so that the speed of a “sperm train” is about 50% faster than that of a single sperm, and that three-quarters of sperm from the same source will join such a queue. The mutual supportive behavior of the sperm does not stop there, as some of the sperm in the “sperm train” will start the reaction mechanism with the egg earlier, which will speed up the whole “train”, but will also lead to the early death of the former. Of course, in the end, only 1-2 Mr. Sperm are lucky enough to unite with Ms. Egg, while the rest of me die within 24-36 hours. But the self-sacrificing behavior of some sperms reflects their value. Having said that, I truly feel that we Mr. Sperm have a very difficult life. We, Mr. Sperm, must have a large number and strong quality, and we need to have both the spirit of solidarity and the spirit of sacrifice in order to fertilize the egg within a limited period of time, so that a new life can be born.