Male reproductive organs include external genitalia and internal genitalia. External genitalia mainly includes penis and scrotum; The internal genitalia mainly includes testis, epididymis, seminal vesicle and prostate. The penis is a male sex organ, and the front end of the penis is the glans penis. In infancy, the glans penis is covered with a layer of skin called foreskin. After accelerating the development of youth, or approaching the mature age, the foreskin will gradually retract, exposing the glans penis. Testis is the most important internal genitalia of men. They are oval and have a pair, which are stored on both sides of male scrotum. During the fetal period, the testicles are in the abdominal cavity and descend into the scrotum after birth. Some boys have no testicles in the scrotum, or only one side has testicles, indicating that the testicles have not dropped in the abdominal cavity, which is medically called "cryptorchidism". Surgery should be done as early as 23 years old. Testis has two main functions: one is to produce sperm; The second is to secrete androgen. Epididymis is attached to testis, and its main function is to store sperm produced by testis. At the same time, the secretion it produces is used for sperm nutrition and promotes sperm further maturity. The seminal vesicle is located at the bottom of the bladder, and its function is to secrete yellow viscous liquid, participate in the composition of semen, and increase sperm motility. Prostate is a solid organ, and its milky white liquid is the main component of semen.

2. The development of male secondary sexual characteristics

With the development of reproductive organs, male secondary sexual characteristics also develop. The so-called sexual characteristic refers to a characteristic that distinguishes men from women. Everyone can determine whether they are male or female at birth, and distinguish them by reproductive organs. The difference between male and female reproductive organs is called primary sexual characteristics, also known as main sexual characteristics. After entering adolescence, the differences in appearance and figure between men and women except genitals are called secondary sexual characteristics, also known as accessory sexual characteristics. The development of male secondary sexual characteristics is mainly manifested in the change of body surface, and the change of hair is the most prominent. 1 1- 12 years old, the vulva has short and thin pubic hair; At the same time, around the age of 12, the Adam's apple of the neck began to protrude, and the voice became louder and thicker. This period is called "voice change period". 1-2 years later, 13 years old and 14 years old began to grow armpit hair. Also began to grow a beard on his face; The hairline of the forehead gradually moves backward, forming a special male hairstyle. The development of male secondary sexual characteristics has turned a naughty and lovely hooligan into a burly, muscular man with a deep and loud voice. So, what is the maintenance of male secondary sexual characteristics? It depends on the androgen secreted by the testis.

3. Male Sexual Physiology and Health

During the development of reproductive system, men will gradually appear some sexual physiological phenomena. Nocturnal emission: Nocturnal emission is a normal physiological phenomenon and a special symbol of male sexual maturity. As we just said, the function of testis is to produce sperm. The boy's testicles have been growing for about a year around the age of 14, and he began to make the first mature seed of life-sperm, and then he made new sperm every day to continue his life. A normal adult man's bilateral testicles produce millions or even hundreds of millions of sperm every day. These produced sperm then reach the tubules that make up the epididymis and stay for about three weeks to complete their maturation. Once the sperm matures, it gradually moves out of the scrotum, enters the body through a tube called vas deferens, and forms semen with milky colloidal liquid secreted by seminal vesicle and prostatic fluid secreted by prostate. When semen is stored in the body for a certain amount of time, it will be excreted if it is not absorbed by the body. This is the reason why the folks say that "the essence is overflowing". Normal young men usually do it once a month 1-2 times. The first nocturnal emission was about 14- 16 years old. About 80% of young men have nocturnal emission from adolescence to marriage. Because most boys have nocturnal emission when they sleep and dream, they are also called "wet dream". If the nocturnal emission is too frequent, there may be a problem and you need to find a specialist for treatment. Of course, people who don't have nocturnal emission should not be uneasy, and don't think that they are sexually and physically stunted. Because semen can also be discharged into the urethra in small amounts for many times and excreted with urine, and I don't know it. Only men with abnormal reproductive organs and undeveloped secondary sexual characteristics, if they have never had nocturnal emission, are abnormal phenomena, and should also go to the hospital for specialist treatment. Although nocturnal emission is a normal physiological phenomenon, it may also be caused by other factors. If life is irregular, the quilt is too heavy to sleep at night, wear tight pants and read pornographic books and periodicals. Therefore, adolescent men should establish a normal life system, establish a correct sexual concept and consciously resist obscene books and periodicals. Need to be reminded that after nocturnal emission, underwear should be changed in time and external genitalia should be cleaned, otherwise the penis foreskin is vulnerable to inflammation.

Masturbation: Masturbation is a physiological manifestation of adolescent sexual maturity and a common phenomenon among adolescents. From a medical point of view, if it is carried out occasionally, it can alleviate the anxiety caused by sexual tension, which is a way of masturbation and has no harm. However, saying that masturbation is harmless does not mean advocating or advocating unrestrained masturbation. Someone once said that when we can control our desires, all desires are good, and when we can't control our desires, all desires are bad. People must not be slaves of desire, and adolescence is a crucial period to cultivate their self-control ability. Just like eating too much food can lead to indigestion, drinking too much wine can lead to drunkenness, and uncontrolled masturbation can also bring negative effects. Frequent masturbation can cause chronic pelvic congestion, causing nocturnal emission, nocturnal emission, prostatitis, perineum, urinary tract sensation, penile pain and dysuria. At the same time, if a person is always shy, sensitive, depressed and withdrawn, and regards masturbation as the only source of satisfaction and tension relief and relies too much, it shows that his psychological development and social adaptability have encountered problems. At this time, masturbation has become a reflection of psychological barriers, inner conflicts and frustration, and it is a pathological manifestation that requires special psychotherapy. So the symptoms at this time are not caused by masturbation itself, but a more complicated psychological disorder. & ltBR & gt& ltBR & gt Too long foreskin and phimosis: Too long foreskin means that the foreskin covers the urethral orifice, but the urethral orifice and glans can still be exposed when the foreskin is upturned. Phycosis means that the foreskin is narrow, tightly wrapped around the penis, and cannot be turned back to reveal the glans penis. The harm of too long foreskin is mainly to affect the local cleaning between foreskin and penis, resulting in skin scales, leading to local redness, itching or pain of foreskin and penis, which is prone to "balanitis prepuce". When the phimosis mouth is too small, it will be difficult to urinate, and urine will often accumulate in the foreskin to form scale and cannot be cleaned. Therefore, both of these situations are unfavorable to reproductive health. You can go to the hospital for examination and treatment, and if necessary, you can do circumcision, and the problem can be solved. There is no influence on the body after operation, and it is also conducive to promoting penis development. & ltBR & gt& ltBR & gt The health care of male sexual physiology is very important to keep the reproductive organs clean. Many boys seldom clean their vulva every day. It is not enough to wash only in the shower. Because a substance similar to white bean dregs grows in the foreskin, called "skin scale", which is most suitable for the growth of bacteria, thus causing inflammation of the foreskin and penis, redness, itching, pain and even adhesion, so that the foreskin can not be turned up. Therefore, it is necessary to develop the habit of washing the lower body with warm water every night, especially for cases where the foreskin is too long or phimosis. When cleaning, turn the foreskin up and wash the dirt with warm water to prevent the dirt from accumulating inside. Of course, if the foreskin is too long, it is best to do circumcision, which is beneficial to reproductive health. In addition, frequent cleaning of vulva can keep anus clean, prevent bacteria from multiplying in perineum and prevent hemorrhoids.