- Male Reproductive System 1-Testes

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- Male Reproductive System
Consists of the two testes (the male gonads), a system of genital ducts,
the accessory glands, and the penis.
1-Testes
Each testis is an oval structure housed in the separate compartment within
the scrotum. It consists of highly tortuous seminiferous tubules that
function in the production of spermatozoa. The lumen of each seminiferous
tubule is lined by a seminiferous epithelium several cell layers thick. The
basal cells of this epithelium are composed of Sertoli cells and
spermatogonia. The latter cells divide by mitotic activity to replicate
themselves and to produce primary spermatogonia. These dipliod primary
spermatocytes enter the first meiotic division, forming secondary
spermatocytes that, by completing the second meiotic division, give rise to
haploid spermatids become spermatozoa, the male gamete.
Small clumps of androgen producing endocrine cells, the interstitial cells
of Leydig, these cells produce the male sex hormone testosterone. Prior to
puberty, testosterone is not produce, but at the onset of puberty the pituitary
gland releases luteinizing hormone (LH) and follicle-stimulating hormone
(FSH).
Sp: spermatids, Sc : spermatocytes , Sm: sertoli nuclei , LC: leydig cells
2-genital ducts
Epididymis
Is consists of head , body and tail.
AT: adipose t. , BV: blood vessel, C: cilia , CT: connective t., P: pigments
3- Accessory Glands
A . Seminal Vesicles
As the seminal vesicles, two highly convoluted tubular structures, join
the ducts. The highly folded mucous membrane of the seminal vesicle is
composed of a pseudostratified epithelium, whose columnar cells are
interspersed with short basal cells, sitting on a fibroelastic lamina propria.
The muscular coat is composed of inner circular and outer longitudinal
layers of smooth muscle and is invested by a fibrous adventitia .
MM: mucous membrane
B. Prostate Gland
The ejaculatory ducts join the urethra as these three structures traverse
the substance of the prostate gland, whose capsule is composed of
fibroelastic connective tissue and smooth muscle cells. The dense stroma
of the gland is continuous with the capsule. The parenchyma of the
prostate is composed of numerous individual glands disposed in three
layers : mucosal, sub mucosal, and external (main). The lamina of
these three groups drain into three system of ducts that lead into the
expanded urethral sinus . The folded mucosa of the glands is composed
of simple cuboidal to columnar epithelia supported by stroma , the
ST: stroma , SM: smooth muscle ,PC: prostastic concretions, BV: Blood vessel
lamina of the glands of older men posses round-to-ovoid proststic
concretions .
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