Male sex organs include penis, scrotum, testes, epididymis, spermatic cord, prostate gland, seminal vesicles, and urethral bulb gland. Those that can be seen are penis and scrotum, which are called external sex organs; those that cannot be seen are epididymis, testes, prostate, seminal vesicles, etc., which are called internal sex organs. First, let’s look at the penis. The penis is an important male sex organ. The penis is divided into three parts: the penis root, the penis body and the penis head. Penis root fixed in the pubic bone, is the penis is not moving part, the penis as a support erection; penis body in front of the root, cylindrical; penis body and penis head junction narrowing, penis head like an officer’s “big hat”, so called the neck for the coronal groove; penis head shape like the head of the turtle, so also known as the glans, is the end of the penis, myxoid expansion It is the movable part of the penis; the front of the head has the opening of the urethra. Many men are very concerned about the size of their penis, always feel that their penis is small, and therefore distressed. Our male penis, withered soft state is about 5-7 cm long, when erect about 10-14 cm long. As long as the erection length is normal, the shorter the atrophy, the more protective effect, peeping at others in the bath, compared with their own, meaningless; furthermore, even if the erection length of the penis is shorter than normal, as long as the erection is normal, generally will not affect the sex life. The length of female vagina is about 8-10cm long, while the outer 1/3 of the vagina is sensitive to touch and the inner 1/3 is insensitive to touch, and no anesthetic is needed when doing electrocautery. So, don’t worry about your short penis, madam is not satisfied. The skin of penis stem is thin and soft, sliding and stretchable, less hairy, the basal layer contains melanocytes, and the melanin grain is large and more, so the color is dark; there are many sweat glands and sebaceous glands on the penis foreskin, which is not often cleaned, there will be prepuce, the prepuce is stimulated for a long time, the incidence of penile cancer is high, and the wife has a high possibility of cervical cancer. If the foreskin is too long, the foreskin can be turned up and the glans can be exposed, so it can be washed frequently without circumcision; if it is circumcised, the foreskin is so tight that the glans cannot be turned out, or the glans can barely be turned out, once erection occurs, circumcision must be done. The foreskin tether is located in the lower part of the penis head belly, inside the foreskin, connected to the glans urethral opening below through the coronal groove. The foreskin tie is not flexible and is often pulled off during sexual intercourse. When circumcision is done, the foreskin tie should be left long enough, otherwise the penis will bend downward when the penis is erect and there will be pain. The mucous membrane of the head of the penis, light red or purple-black in color, cannot slide, cannot be stretched, and has no hair; there are rich nerve fiber endings, which is the strongest and most concentrated part of male sexual sensation. The penis has 3 spongy bodies, including 2 penile corpus cavernosum, together on the dorsal side of the penis; 1 urethral corpus cavernosum, on the ventral midline, to the expansion of the spongy body at the head of the penis, forming the head of the penis, with the urethra passing through the middle. The penis is erect because the cavernous body is engorged with blood, the volume of the cavernous body increases, and the outer white membrane of the cavernous body is tough so that the cavernous body will become hard. A fully erect penis can be broken by trauma, such as incorrect sexual intercourse position. The function of the penis is, firstly, a sexual receptor, which is very sensitive; secondly, an organ of intercourse, which replaces the penis bone; and thirdly, an organ of urination. The scrotum is located underneath the penis, with a median septum right in the middle, dividing the scrotum into two cystic cavities on the left and right; each side of the scrotum has testicles, epididymis and lower section of the spermatic cord, one on each side. The scrotum has thin skin, rich in sweat glands, hair follicles and sebaceous glands, and is moist when sweating, smelly when not washed in time, stretchy, black and wrinkled. The scrotum is soft, elastic, cushioned and mechanically protective of the testicles; the rise and fall of the scrotum can regulate the temperature inside the scrotum, the temperature needed for sperm production is 35.5 to 36°C, 1 to 1.5°C lower than the body temperature (new literature new values up to 6°C), wearing tight pants and frequent sauna baths can affect sperm viability. The scrotum is also a sexually sensitive area to obtain pleasure during sex. The testicle is ovoid, inside and outside both sides of the face, front and back two edges, upper and lower ends, size 3.5 × 2.3 × 1.7 cm, about 15 g. The posterior side is connected to the epididymis, there are spermatic cords hanging inside the scrotum, the surface is smooth, except where the epididymis is covered, except by the sphincter dirty layer The outer layer of the testicle, is a whitish and tough connective tissue membrane, 0.5 mm thick, called white membrane. There are 100-300 testicular lobules in the testis, each lobule is cone shaped and contains 2-4 varicose sperm ducts, which are responsible for the production of sperm and androgens. The testis is wrapped outside by the sheath, which is divided into a dirty layer and a wall layer, and the cavity between them is the sheath cavity, which contains the right amount of exudate and has a lubricating effect to prevent and control testicular trauma. At birth, the testicle descends to the scrotum. If it does not come down, it is called cryptorchidism. If the testicle does not come down in the body, the temperature in the body is high and the testicle will be damaged, which will affect fertility and is also easy to get testicular cancer. Therefore, when cryptorchidism is found, surgery should be performed in time to pull down the testicles. The best time for surgery is before 2.5 years old. If the surgery is done after 2.5 years old, even if the testicles are pulled down, it may affect fertility after growing up. Adults with cryptorchidism should also have surgery, the purpose is, once there is cancer in the testicle, it can be detected in time. The function of the testicles is to produce sperm and secrete sex hormones. The epididymis is on the dorsal side of the testicle and is divided into three parts: the head, the body and the tail. The head is at the upper pole of the testis, the body is at the posterior part of the testis, and the tail is at the lower pole of the testis. It is about 6cm long and 0.5cm in diameter. 10-15 tubules depart from the testis, penetrate from the testis into the epididymis, and finally converge into a small tortuous tube. The tubules are 4-6m long and 0.5mm in diameter, i.e. the epididymal duct. The functions of the epididymis are, firstly, absorption and secretion. 99% of the testicular network fluid is absorbed at this epididymal head, secreting carnitine, glycerol phosphorylcholine, salivary acid glycoprotein, etc. Secondly, it is a sperm storage environment, which is conducive to sperm being in a resting state and prolonging sperm survival time up to several months. Third is the high hormonal environment, with high androgen levels in the epididymal body and gradual sperm maturation for about 19-25 days. Fourth is the immune barrier function, similar to the blood-testis barrier. Fifth is the contractile function, the head and body normally contract rhythmically, the tail normally does not contract and contracts during ejaculation. The spermatic cord contains the vas deferens, arteries, veins, nerves, and foveal tissue. The total length of the vas deferens is about 40 cm, divided into the testicular part, the spermatic cord part and the pelvic part. The abdominal part of the vas deferens is called the ejaculatory duct after converging with the seminal vesicles. It is composed of three layers of smooth muscle: inner longitudinal, middle longitudinal and outer longitudinal, and acts as a channel for sperm discharge. After vasectomy, sperm cannot be expelled and contraception is available. Varicocele, a common condition. The venous return is blocked and venous blood accumulates around the testicles, which can be damaged due to increased pressure, temperature, harmful substances and lack of oxygen. First, it may affect the quality of sperm and affect fertility, and second, it may affect hormone secretion, which has an impact on men’s health and requires treatment. The prostate gland is located in the pelvic cavity, under the bladder. It is inverted and conical in shape, with a urethra passing longitudinally from the gland, connected at the bottom up to the bladder and at the tip down to the superior fascia of the urogenital septum. The pubic symphysis is anterior and the rectum is posterior. It is composed of glandular and muscular fibrous tissue. It is about 2.5cm long, 3cm across, 2.5cm thick and weighs about 18g. As a simple analogy, the normal prostate is usually the size of a pigeon’s egg, but if it increases to the size of an egg, or larger, it may be a prostate enlargement, or other prostate disease. The prostate gland is involved in sex and reproduction, secreting prostate fluid, accounting for 1/3 of semen, therefore, prostate disease, which may affect fertility; the prostate gland wraps around the urethra, therefore, prostate disease is often related to urination, such as prostatitis can appear frequent, urgent, painful urination, urine are dripping white, etc., prostate hyperplasia can appear difficult to urinate. The spermathecae are behind the bladder, the upper posterior part of the prostate, outside the end of the vas deferens, before the rectum, a pair of cystic organs, 2.11-6.16cm long, 2cm wide, volume 4ml. the role of the spermathecae, one is to secrete seminal fluid, accounting for 70% of semen. Secondly, it produces fructose, the energy supply of spermatozoa. Third, it produces prostaglandins, which loosen the cervix and facilitate fertilization. Fourth, it secretes protease, which protects sperm. The urethral bulb glands are located in the deep perineal sac between the upper and lower fascia of the urogenital septum, on either side of the membranous urethra and above the posterior urethral bulb. A pair of pea-sized, solid, yellowish-brown round bodies with glandular ducts pass through the urethra and open at the proximal end of the bulbous urethra. The function is to secrete a little urethral bulb glandular fluid when sexually excited, lubricating the seminal tract, lubricating the glans and foreskin.