genital apparatus

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I- L’ MALE REPRODUCTIVE SYSTEM :

Still called « male reproductive system », it includes’set of organs that participate in the reproductive function. It matures late and does not become fully functional until’at puberty.

It has two functions :

  • exocrine function : l’emission of sperm
  • endocrine function : production’male sex hormones (mainly testosterone).

L’appareil génital comprend :

  • the gonads (or testicles) (T)
  • The genital tract : straight tubes, efferent ducts, epididymis (E), vas deferens (D), ejaculatory duct and urethra (The).

This last segment, impair, est commun à y l’appareil reproducteur et à l’Urinary System.

  • Glands attached to the genital tract : seminal vesicles (VS), prostate (P) and Cowper's glands (C).
  • The external genitalia : penis and scrotum.

Anatomy of the male reproductive system

1- external genitalia :

The external genitalia include the penis and scrotum.

the penis :

Encore appelé verge est lorgane qui assure l’éjection du sperme, called ejaculation, at the time of intercourse ; it also allows the’evacuation of’urine.

The penis consists mostly of 2 cavernosa and a spongy body.

When a man is sexually aroused, these organs swell with blood and the penis hardens : This is the erection.

the acorn, is the rounded end of the penis. At the end is a hole, urinary meatus. The glans is covered by a skin, le prépuce.que lon excise souvent chez les nouveau-nés pour des raisons sanitaires ou religieuses. L’ablation du prépuce est connue sous le nom de circoncision.

the scrotum :

The scrotum is a bag of skin more or less wrinkled, generally more pigmented than body skin (darker), hairy. The scrotum is divided into two compartments, scholarships each containing a testicle, Instead of producing sperm

2- internal genitalia :

They are composed by : the testicles, epididymis, vas deferens, urethra, glands (seminal vesicles, prostate, Cowper's glands).

The testicles :

During fetal life, the testicles are located in the abdomen. Before birth or immediately after, they leave their positions to take to the scholarships because body temperature is too high for sperm production. The location of the scrotum gives a temperature between 34 and 35 degrees.

The testicles are the male gonads, producing sperm. these glands, oval, two in number, are about 3.8 cm long and 2,5 cm diameter. The testicles have a dual function, exocrine (sperm formation) and endocrine (secretion of male hormones by the Leydig cells, located between the seminiferous tubules). visit’man, testes are enclosed in a double outer pocket, called scrotum (bourses). Each gland is enveloped by a fibrous membrane, strong, resistant, d’un blanc nacré et quon nomme albuginée.

The testis is surrounded by a connective capsule, l’albuginée (A).

The capsule thickens superior-posterior pole, forming the body of Highmore (H).

The testicle contains 200 at 300 lobules (L), triangular section on, limited by connective tissue septa. Each lobule contains 1 at 4 seminiferous tubules (or better seminiferous) that coalesce into a straight tube.

The straight tubes represent the first segment of the genital tract and flow into the rete testis. C’is an anastomosed intra-testicular network which continues through the efferent ducts and then through the’epididymis.

a- The epididymis :

The epididymis (E) I cap testicle as a helmet crest. 1-has the thickest part, the upper pole, s’call the head of the’epididymis. It contains the efferent ducts. The bottom part, or tail of the’epididymis, continues with the vas deferens (D).

The epididymis is a small elongated member, located on the posterior upper edge of the testicle. It consists of the epididymal duct curled on itself, whose function is the storage of sperm, from testis, and extends through the vas deferens. The sperm remain in the epididymis in rope form until ejaculation, when’they are ejected into the vas deferens, which leads the sperm to the’urethra. The epididymis is where mature sperm, they are naturally replenished and where they are destroyed if there is no sex.

The testicular lobule :

It consists of the interstitium and tubules, where spermatogenesis takes place.

The interstitial tissue :

This is the loose connective tissue, rich in blood and lymphatic capillaries. It contains pockets of Leydig cells, constituting the testicular interstitial gland. C’est une glande endocrine diffuse. It represents about 3% testicular volume. Leydig cell develops testicular androgens, mainly testosterone that synergy with FSH (d’origine hypophysaire), ensures the maintenance and’germline integrity. Testosterone acts on many other tissues : bone, muscle tissue, skin and its annexes.

The seminiferous tubules (or séminipares) :

The seminiferous tubules are bypassed. They are about lm long and 150 at 180 pm diameter.

They are surrounded by a connective tissue sheath, the peritubular sheath (or own membrane) et sont bordés par l’seminal epithelium, resting on a basement membrane.

The seminal epithelium :

It is about 70 d pm’épaisseur et comport 2 .cell types : germ cells and Sertoli cells.

Sa structure nest bien apparente qu’Electron microscopy.

The cells of the germline (33% testicular volume) :

their evolution, during spermatogenesis, is done in the’thickness of l’epithelium, with migration from the periphery toward the tube lumen.

They comprise successively :

  • The stem cells or spermatogonia (Sg). These are the devices. They divide giving’une part une nouvelle cellule souche et d’autre part une cellule évoluant vers la spermatogenèse.
  • The primary spermatocytes (S I), then secondary
  • spermatids (Sp)
  • sperm (spz).

Meiosis occurs at the stage of spermatocytes. The first division, reductional, provides the primary spermatocyte crossing secondary spermatocyte. The second, equational, gives spermatids, haploid.

Spermatids undergo differentiation, the spermiogenèse, which results in the release of the spermatozoa into the lumen of tube (spermiation).

Sertoli cells (S) :

These are large somatic cells that s’extend from the basement membrane to the lumen of the tube. Their lateral faces are depressed to accommodate the neighboring germ cells. They have a support role for the germ cells and are essential to the success of spermatogenesis. They differ little before puberty.

To the external third of the’epithelium, exists between Sertoli cells, tight junctions (J) separating the seminal epithelium 2 compartments :

  • An outer compartment where the youngest cells are located (spermatogonies et spermatocytes I).
  • An internal compartment, abluminal, containing the most advanced elements. Sertoli cells are the only intermediaries between the internal compartment and the rest of the’organization. They participate in the barrier blood-seminal (blood-testis).

Sertoli cells do not multiply.

The functions of the Sertoli cells :

  • Drawing the liquid contained in the seminiferous tubules.
  • Support and nutrition to the germ cells. They produce lactatc and pyruvate.
  • Production d’ABP (Androgen Binding Protein)
  • hormonal functions : Elles contrôlent lenvironnement hormonal de la spermatogenèse en concentrant la testostérone produite par les cellules de Leydig.
  • They produce inhibin which inhibits pituitary FSH secretion, et racUvine dont leffet est inverse.
  • They control spermiation.
  • They phagocytose and destroy cytoplasm fragments removed by spermatids (residual body) and destroy the germ cells degenerate.

The vas deferens :

Long de 45 cm, extends the epididymis and ensures the transit of sperm to the urethra.

When a man uses a vasectomy (equivalent to tubal ligation in women), severs the surgeon ligation or the vas deferens through an incision in the scrotum. This procedure prevents sperm from reaching the prostate, the ejaculated semen contains only the seminal fluid. Sexual performance are not affected so far.

The urethra

. L’urètre prend naissance à la base de la vessie, through the cavernosa of the penis and ends with the urethral meatus (orifice), at the top of the glans penis. L’urètre masculin transporte à la fois l’urine (bladder) and glandular secretions of the testicles (whose sperm ejaculatory duct) à travers le pénis jusquau méat urétral. It is the only channel where the throw is 2 vas deferens. This end portion, common to the urinary system and genital system, routes depending on the circumstances. Urine or sperm outside the body.

b- The glands :

These are 2 seminal vesicles, prostate and Cowper's glands

The seminal vesicles :

Ensure the secretion of’a liquid used in the composition of sperm, when the sperm pass into the vas deferens. Both vesicles resemble small pockets bulbous located just above the prostate.

prostate :

Is composed of smooth muscle and glandular tissue. Elle entoure la partie initiale de l’urethra, just below the bladder. D’a diameter d’about 38 millimeters, the prostate secretes a clear liquid that’she pours into the’urètre au moment de l’excitation sexuelle. This alkaline fluid precedes the sperm and helps reduce’acidité des sécrétions vaginales afin quelle ne provoque pas la destruction des spermatozoïdes.

Les glandes bulbo-urétrales :

(Cowper's glands) sont deux lobes de la taille d’a pea on both sides’other of the’urethra and secrete a lubricant into the’urètre afin de faciliter le transport des spermatozoïdes au moment de l’éjaculation.

II- REPRODUCTIVE WOMEN :

It consists of:

  • The 2 ovary or gonads
  • The genital tract or genital tract :
  • The fallopian tubes or oviducts 10 at 12 cm de long. their flag, lined with fringes, s’ouvre dans la cavité péritonéale et coiffe l’ovary. Il se poursuit par l’ampoule, puis par listhme et enfin par la partie interstitielle qui souvre dans l’utérus.
  • L’uterus, organe musculaire où seffectue la nidation, and pregnancy. The body, triangular, continues through the cervix opens into the vagina.
  • the vagina with glands.
  • The external genitalia.

1- The external genitalia :

Les organes génitaux externes de la femme sont plus discrets que ceux de l’homme et davantage dissimulés à lintérieur du corps.

The outer part : vulva

It involves :

a- the labia majora, which are two folds of skin usually more pigmented than the rest of the body and covered with hair from puberty. They cover the’opening of the urinary and vaginal ducts. Their appearance and size vary according to women.

b- labia are two folds of skin color rosacea, lying at the’inside of the labia majora. Elles peuvent presque être absentes chez certaines femmes alors que chez d’other, they can be highly developed to the point protrude between the labia majora. They swell and turn red with blood flow during sexual stimulation. They contain two openings: one tiny, the urethra to drain urine, the other corresponding to the vagina.

c- The hymen firm partly the vagina. C’est une mince membrane qui peut rendre le premier rapport sexuel plus ou moins douloureux et même provoquer un écoulement sanguin lorsqu’he is perforated. C’est par la présence de lhymen qu’on détermine la ’’virginité » d’une fille.

d- the clitoris : The labia also covers the clitoris, small outer fabric bud. It is the equivalent of the glans penis (clitoris and penis have the same embryonic origin). It is located at the junction of the labia minora towards the’before. Il est recouvert d’a cap (equivalent of the foreskin), formed in part by the labia minora.

e- Bartholin's glands two in number, located on both sides’other of the’orifice vaginal, secrete a few drops of’un liquide lubrifiant au moment de l’excitation sexuelle. They are the equivalent of Coxvper glands of man.

NB : on appelle périnée la région en forme de losange comprise entre le bord antérieur des grandes lèvre^ et l’anus. This true pelvic floor muscles together is very important because it supports the internal organs (bladder, uterus etc.).

2- The internal genitalia :

The internal genitalia of women include : the ovaries, the fallopian tubes, l’uterus and vagina

a- ovaries :

The gonads of women or ovaries, two in number, are located on either side of the’uterus and held in place by different ligaments. They are the size of’une grosse amande Ils ont pour fonction de produire les ovules, d’ensure their maturation and synthesize female hormones, estrogen and progesterone.

histological structure :

On distingue:

  • epithelial ovarian, cubic
  • Ovarian tunica
  • the cortical region which contains the ovarian follicles at different stages of their evolution
  • medullary region with a conjunctive parenchymal area and a fibrous hilar area

b- The fallopian tubes :

Les trompes sont deux conduits étroits d’about 10 cm, that start from the bottom of the uterus to move towards each ovary but without direct contact with them. La partie des trompes près de lovaire s’expands to form a fringed cone, Pavilion. At the time of’ovulation, les franges viennent saisir l’ovule pour laider à passer dans le pavillon. Puis l’ovule remonte la trompe jusqu’à l’uterus. Les trompes sont le lieu où lon peut effectuer aussi la stérilisation de la femme; this operation s’called tubal ligation.

The tube is made up of four portions:

– Pavilion- bulb- the Isthmus- interstitial portion

During the’ovulation, tubal fringes approach the ovary and pick up the oocyte cumulus surrounded and part of the follicular fluid. The progress of the oocyte is provided by the contraction of the muscularis,the beating of cilia and liquid flow tubal The trunk by its contractions also promotes sperm transport to the site of fertilization Tubal Fluid allows survival of the egg

c- L’uterus :

L’uterus is a hollow organ d’about 7,5 cm long 5 cm wide, in form of an inverted pear, located above the bladder and securely anchored by ligaments. L’uterus divides into three parts : the bottom of which the two tubes depart, the body, upper part strongly muscled and capable of’significant increase in volume during gestation and cervix, narrowest part that protrudes into the vagina and which secretes a mucus called cervical mucus.

L’orifice du col est une petite ouverture qui permet l’entrée des spermatozoïdes dans l’uterus, the outflow of menstrual blood and which can s’enlarge more than ten centimeters when’delivery. C’est dans le corps de l’womb that s’implante l’œuf fécondé et que se formera par la suite le Placenta qui assure les échanges entre le fœtus et le corps de la mère.

The uterine wall comprises 3 tunics:

  • mucous (endometrial)
  • the muscular (myometrium)
  • serous
  • The endometrium : The mucosa has a prismatic simple epithelium with ciliated cells and secretory cells. The lamina propria contains glands and abundant vascularization.
  • The myometrium .Constitué bundles of smooth muscle fibers.
  • serous : Nature elastic connective tissue

The cervix :

We must distinguish the endocervix and ectocervix

Endocol : – Simple columnar epithelium with numerous mucous secreting cells and some glands hair- choricn dense that contains glands

Exocol : – multilayered squamous non-keratinized with absence of glands in the lamina propria

The secretory cells of endocervical develop cervical mucus whose quantity and quality vary during the menstrual cycle.

The mucus is abundant with the approach of ovulation.

Mucus peri-ovulatory (the 14th day of lOémc) is spinning, has its maximum hydration and has a pH between 7 and 8,5 and has antibacterial activity.

Apart from the peri-ovulatory, the mucus is scarce, highly viscous, and has meshed. This mucus appears under the influence of progesterone and persists until the next cycle Tenth day.

d- the vagina :

The vagina is a thick muscular organ shaped tube 7 at 10 centimeters Length, located between the vulva and the cervix’utéras. It allows the release of menstrual flow during menstruation and the passage of the baby during delivery (its expansion capacity is very large). It is moistened and lubrifïépar cervical mucus.

This is a conduit musculo-membranous whose wall consists of 3 couches: mucous, muscular and weed.

Organisation générale de lappareil génitale féminin

Courses of Dr. Hannachi – Faculty of Constantine