Male Reproductive system of Human PDF Print E-mail
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Written by punjalak   
Tuesday, 29 July 2014 05:08

The male reproductive system is located in the pelvis region. It includes a pair of testes along with accessory ductglands and the external genitalia. It consists of a pair of testis lodged in an integumentary pouch - the scrotum. Initially they are abdominal, however as the development proceeds they descend down into the scrotum. It has been proved that this adaptation enables regulation of internal temperature of the testes higher than body temperature which is essential for their normal functioning.
In adults, each testis oval in shape, with a length of about 4 to 5cm and a width about 2 to 3cm.
The testis is covered by a dense covering, each testis has about 250 compartments called testicular lobules. Each lobule contains one to three highly cord somniferous tubules in which sperms are produced. Many such somniferous tubules after exit again from a complex network of tubular system known as rete-testis. Small ducts from rete-testis again unite to from a large convoluted duct called as epididymis, in which sperms are stored. Epididymis continues into vas deferens which carry sperms away from the testis. Vas deferens after curving back over lower abdominal area enlarge to form ampulla, in which opens a coiled tube with sacculated walls; this is the seminal vesicle. It is supposed to perform nutritive function by providing fructose and other nutrients to maintain vitality of sperms. By the union of seminal vesicular ducts and vas deferens a short canal is formed is called as ejaculatory duct which further unites with the ureter to from a common passage the urethra - which opens to outside of the body through the penis. Seminiferous tubule is lined on its inside by two types of cells called: Male germ cells undergo meiotic division finally leading to sperm formation. Sertoli cells provide nutrition to the germ cells. Outside of Seminiferous tubules called interstitial spaces, contain small blood vessels and interstitial cells or Leydig cells. Leydig cells synthesise and secrete testicular hormones called androgens. Other immunologically competent cells are also present 

Two glands - prostate and bulbourethal (Cowper's) glands open into the urethra.
They produce mucus that lubricates the urethra to facilitate the ejaculation of sperms during copulation.
Secretions of these glands constitute the seminal plasma which is rich in fructose calcium and certain enzymes.
External genital organ in male is penis through which urethra runs. It is an erectile organ and helps in sperm deposition in the vagina during copulation.

ที่มา : http://www.youtube.com/channel/UCflmr7Tyyy38MaAENetim_g อัพโหลดโดย 7activestudio

Last Updated on Wednesday, 30 July 2014 04:58
 

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