Egg

Egg - steam male sex gland, which is education male sex cells - sperm - and produce male sex hormones.
The testicles are located in the scrotum (see), usually the left testicle below right. Adult Mature men egg represents the body of the ovoid shape with an average size of 4,5X2,5X3 cm, weight 15-25 years Before puberty egg has a significantly lower and tablevalue consistency in the pubertal period, the testicle increase. The testicles (Fig. 1-3) covered with a dense connective tissue tunica which goes radial partitions, dividing the testicle into slices. Fabric (parenchyma) testicular consists of numerous seminiferous tubules, lined with epithelial Sertoli cells, which are involved in spermatogenesis, i.e. in education male sex cells. Between the Sertoli cells are the primary germ cells - spermatogonia, which are sperm cells at different stages of development. Between the seminiferous tubules are interstitial Leydig cells involved in the formation of sex hormones. On top of the tunica egg covered with vaginal membrane consisting of two sheets. In some diseases between the shells may accumulate fluid (see Hydrocele). To the rear edge of the testis is adjacent Annex (epididymis)from the efferent tubules, turning into the duct of the epididymis, and continuing in the ductus deferens. The testicle with the epididymis and seed cord directly surrounded by the inner seed fascia and outwards - fibers of the muscles that raise the testis and its fascia.

the testicles are the male structureFig. 1. The external surface of the right of the testis and epididymis: 1 - domestic seed fascia; 2 - own vaginal membrane of the egg; 3 - head of the epididymis: 4 egg; 5 - scrotal bunch of eggs (sender); 6 and 7 - the body of the epididymis.
Fig. 2. The back surface of the vessels of the right of the testis and epididymis: 1 - botryoidal plexus; 2 - testicular artery; 3 - the head of the appendage; 4 - body of appendage; 5 - testicular parenchyma; 6 - tail appendage; 7 - artery VAS duct; 8 - the ductus deferens; 9 - internal seed fascia.
Fig. 3. Sagittal section of the testis and epididymis: 1 - cylinder, appendage; 2-efferent ducts egg; 3 - lobes eggs; 4 - network of the testis; 5 - mediastinum egg; 6 - duct appendage; 7 - protein shell of the egg; 8 - the ductus deferens; 9 - tail appendage.

In the fetus egg develops in the lumbar region and by the time of birth descend into the scrotum. The delay of the testicle into the abdominal cavity or inguinal canal is called cryptorchidism (see). The main method of investigation of the testis is palpation.

Egg (testis) - pair glandular organ, ovoid shape, flattened on the sides. The length of the egg is equal to 4-5 cm, width and height of 2.5 - 3 see the back of the testicle adjacent appendage it (epididymis) - oblong body length of 5-6 cm, thickness 0.5-sm In the epididymis distinguish the upper end (head), which is fixed to the upper pole of the testicle, the middle part (body), the loose fibre bound with the back edge and the bottom end (tail), adjacent to the lower pole of the testis.
Fabric testicular spliced with its surrounding tunica. Last surrounded actually vaginal membrane consisting of two sheets - visceral and parietal. The testicle with the appendage surrounded total vaginal sheath associated with muscle bundles, which cover the egg and form the muscle that raises the testicle (m. cremaster). The lower pole of the testis is fixed to the internal surface of the bottom of the scrotum Gontarovsky ligament.
Protein membrane forms on the back edge of the testicle enlargement, called the maxillary body, from which the fan-shaped diverge connective tissue septum that divides the parenchyma of the testis in the vertical direction 200-300 slices. The segment consists of a long, tortuous seminiferous tubules that connects near the maxillary body in a straight tubules that come into maxillary body and make up there hallerowo network. In this place straight canals are connected in 10-12 larger efferent tubules that were sent to the head of the epididymis and unite in one winding channels - body appendage;
the last in the tail Department bent backwards up and goes into the ductus deferens (Fig. 6).
Seminiferous tubules of the testes consist of semibratowo epithelium and sartayevich cells. Between the tubules are Ladyhawke cells, which attributed the bulk of hormonal function of the testis. The blood supply of the scrotum comes from a. spermatica interna and a. spermatica externa. The outflow of blood is made through venous plexus - plexus pampiniformis, which is part of the spermatic cord and drains into the spermatic vein.
The lymphatic vessels of the testicle go to the lymph nodes located along the external iliac vein, the aorta and inferior Vena cava.
Testicles reach full development with the onset of puberty (16-18 years). Spermatogenic their function is saved to a ripe old age.
Simultaneously with the spermatogenic develops and vnutricletocny function of the testis, which basically consists in the development of the male sex hormone testosterone and to a lesser extent other androgens. Among the latter the most important are the 17-ketosteroids. Daily allocation of 17-ketosteroids in urine is in men 1-30 mg, women - 1-20 mg the Average figure for the age of 20-30 years men 15 mg, women 10 mg there are alpha - and beta-faction 17-ketosteroidov. The first corresponds to the testicular hormones, and the second to hormones . adrenal gland. In norm the ratio between them is 10: 1. The change in the direction of increasing p-fraction suspiciously at the tumors of the adrenal gland (hyperthyroidism of the adrenal gland).

Fig. 6. The testicles, epididymis, and the ductus deferens.

Egg (testis; synonym: testis, testiculus, orchis, didymis) - steam room male sex gland, which is education male sex cells - sperm - and produce male sex hormones.

Embryology
On 4-5 weeks embryonic period is formed pair of oblong genital exaltation on each side of the spine in the area volfova body (primary kidney). Primary sexual cells travel to the genital rollers and are immersed in them. Further, the cells Zacatecoluca epithelium, multiplying intensively, grow into mesenchyme in the form of fibers, containing the sex cells. From Zacatecoluca epithelium formed seminiferous tubules. After 3 months of embryonic period of the testis due to the proliferation of connective tissue takes a rounded shape, and form a mesentery of the testis.
Further seminiferous tubules are grouped so that the egg is divided into conical sectors facing peaks to the mediastinum testicles and foundations - to formed from connective tissue protein shell.
In the mediastinum testicles develop a network of eggs, from which begins the tubes that carry sperm formed from elements of primary kidney and volfova duct. The tubes that carry sperm unite, become sharply convoluted shape and form of the epididymis (epididymis).
By the beginning of the 7th month of the embryonic period, the egg goes down to the inner hole of the inguinal canal and on the 8th month falls in the inguinal canal, and then into the scrotum. The egg down the rail link - gubernaculum testis (Hunteri)coming from the lower pole of the testicle into the scrotum, where is attached in the form of a fan. The mechanism of the descent of the testis due to the topography of organs (kidneys, intestines) due to their growth, tension shrinking guide ligaments of the testis and hormonal effects, in particular gonadotropic hormone.

Anatomy
The egg is oval, flattened laterally. Its length is the average adult is 4-4,5 cm, width - 2,5-3,5 cm, the thickness of 1,8-2,4 see the Weight of the testis 20-30, Is the testicle into the scrotum, usually left lower right. The epididymis is located on the upper pole and the rear edge. The surface of the egg is covered with vaginal sheath (tunica vaginalis propria), formed from vaginal process of the peritoneum and consisting of two sheets - parietal and visceral, between which there is a gap (Fig. 1-3).

anatomy of the testis
Fig. 1. The external surface of the right of the testis and epididymis: 1 - fascia spermatica; 2 - tunica vaginalis testis; 3 - caput epididymidis; 4 - testis; 5 - lig. scrotale testis (gubernaculum); 6 - lig. epididymidis inf.; 7 - corpus epididymidis; 8 - epididymis.
Fig. 2. The back surface of the vessels of the right of the testis and epididymis: 1 - plexus pampiniformis; 2 - a. testicularis; 3 - caput epididymidis; 4 - corpus epididymidis; 5 - testis; 6 - cauda epididymidis; 7 - a. ductus deferentis; 8 - ductus deferens; 9 - fascia spermatica interna.
Fig. 3. Sagittal section of the testis and epididymis: 1 - caput epididymidis; 2 - ductuli efferentes testis; 3 - lobuli testis; 4 - rete testis; 5 - mediastinum testis (Highmori); 6 - ductus epididymidis; 7 - ductus deferens; 8 - cauda epididymidis.


Visceral sheet tightly adherent to the tunica (tunica albuginea) 0.5 mm thick, forming on the back of the rear edge of the egg thickening, protrude inside the testicles - mediastinum testicles or maxillary body. Depart from it connective tissue plate that separates the parenchyma of the testicle into slices (150-250). Clove is 3-4 convoluted tubules (tubuli seminiferi contorti), passing in the mediastinum in the direct channel (tubuli seminiferi recti). Direct form a network of tubules of the testes (rete testis). From the network goes 7-18 efferent tubules (ductuli efferentes walking through albuginea into the head of the epididymis, where they come together, form a duct tortuous appendage. The epididymis is divided into head, body and tail. Head spliced with the upper pole of the testicle, the body is attached to the rear edge of the testicle, tail separated from the egg layer of fiber. The duct of the epididymis, coming out of the tail of the epididymis, goes into the ductus deferens, going up steeply.
The blood supply to the testicle is mainly due to a. spermatica interna (s. testicularis), departing from the abdominal aorta and running as part of the spermatic cord; venous outflow through plexus pampiniformis and v. spermatica, and left the seminal vein drains into the left renal vein and the right into the inferior Vena cava.
Lymphatic vessels testicular parenchyma and the tunica widely anastomosis. Coming out of the mediastinum, they form larger lymphatic trunks, which are in the composition of the spermatic cord on both sides to regional lymph nodes located right at the confluence of seminal vein in the hollow, and the left - under the left renal vein. Innerviruetsya egg sympathetic and parasympathetic nerves.

Histology
Testicular parenchyma form mainly of convoluted tubules, surrounded by connective tissue, richly permeated with blood and lymph vessels. In the connective tissue of the testicle, besides the usual cellular elements (macrophages, fibroblasts and others)have special interstitial, or interstitial, Leydig cells - large polygonal cells with large kernel, located usually in groups. Leydig cells are a function of education sexual hormone.
The formation of sperm, or sperm cells, occurs in the tortuous seminiferous tubules, which has a diameter of 0.15-0.25 mm in length from 30 to 70 cm Wall convoluted tubule formed of several layers of flat connective tissue cells, elastic and collagen fibers. The inner layer forms the basement membrane, which are epithelial cells Sertoli involved in spermatogenesis, i.e. in education male sex cells. Between the Sertoli cells are primary sexual cells spermatogonia. Since sexual maturity they begin to re-share, forming the spermatocyte - larger cells with a large nucleus, which lies at the next layer. From spermatocyte division formed spermicide. Their maturation occurs during intensive participation of Sertoli cells. Head of Mature sperm cells embedded in the Sertoli cells, cytoplasm which surrounds them. Thus the transport of nutrients to the growing sperm. The latter, having ripened, fall off and are in the lumen of the tubule and then move forward with cilia epithelium efferent tubules.

Physiology
Egg carries out the function of reproduction in a male body in two ways: exocrine, i.e. through the development of male sex cells (sperm), and vnutricletocnam, i.e. through the development of male sex hormone.
Male sex hormone produced in interstitial the Leydig cells and enters the bloodstream. The maximum number of Leydig cells marked in the period of sexual maturity. Consequently, entering the body sex hormone causes intensive development of secondary sexual characteristics and spermatogenesis. In old age the number of Leydig cells decreases and decreases the production of the male hormone. When castration is reduced or disappears sexual feeling and secondary sexual characteristics undergo reverse development.
Vnutricletocny function of the testis is in interaction with the functions of the other endocrine glands. The greatest influence on the function of the testis have gonadotropic hormones of the anterior pituitary gland that stimulates spermatogenesis and production of sexual hormones (see). Direct connection there is between a function of the testes and adrenal glands that if the flow in the body's sexual hormone partly take over the function of the testis. Very closely function of the testis connected with the activity of the Central nervous system, particularly the hypothalamus.

Research methods
During the inspection and palpation is possible to identify increase pain and testicle (orchitis); bumpy surface and weight gain (tumors); abnormalities of the number and status. For differential diagnosis of tumors of the testis and hydrocele (see) apply diaphanosoma - screening of the scrotum in a darkened room.
For a number of diseases of the testis and epididymis used needle or the operating biopsy, and x-ray - epididymography in tuberculous lesion, lymphangiography with the introduction of contrast agents in the lymph vessels of the spermatic cord or lower extremities for the detection of metastatic tumors of the testis.
Of laboratory methods are widely applied research ejaculate (see Sperm). If you suspect a testicular tumor produce Elgama - Condeca reaction (see). Urine selection of 17-ketosteroids and other hormones is set in the absence of the testicle into the scrotum, with evnuhoidizme.