Male reproductive system consists of testes, vasa efferentia and urinogeniteal ducts. Copulatory organs are absent.
1.Testes: A pair of testes are present. Each testis is an elongated or ovoid, light-yellow Coloured structure attached to the antero-ventral surface of each kidney by a double fold of peritoneum called mesorchium. Near the anterior end of testis arise several branched finger-like fat bodies which stores reserve food to nourish developing spermatozoa and during hibernation.
Histologically, each testis is a compact mass of much coiled seminiferous tubules in the mass of connective tissue. These Seminiferrous tubules internally remain lined by epithelial cells called as primordial cells. These primordial cells undergo the process of spermatogenesis to form sperms. The process of formation of sperms is called as spermatogenesis.
In the space between these seminiferous tubules interstitial cells or Leydig's cells are present which are endocrine in nature and produce male sex hormone , testosterone which is responsible for the development of copulatory pad and vocal sacs in male frog and also help in spermatogenesis.
2. Vasa efferentia: All the seminiferous tubules inside a testis are connected to form 10 to 12 narrow tubes, the vasa efferentia. They emerge out from the testis, run through mesorchium and enter inside the kidney and open into the Bidder's canal. The Bidder's canal is a vertical canal inside kidney and is connected to the ureter through collecting tubules of kidney. Thus, Function of vasa efferentia is to carry mature spermatozoa from testis into Bidder's canal of kidney.
3. Urino-genital ducts : The Bidder's Canal inside Kidney continues out from posterior end of kidney as ureter.The Ureter in male frog is both a urinary duct and vas deferens i.e. carries both urine and sperms.Hence, it is called as urino-genital duct. The urinogenital ducts of both the sides run posteriorly and open into roof of cloaca separately on urinogential papillae. In some species of frog, the urinogential ducts are enlarged near kidneys forming seminal vesicles for temporary storage of spermatozoa until needed.
The function of Urinogenital ducts is to carry Urine and sperm upto cloaca.
The cloaca is a sac like structure and is Common passage for undigested food, metabolic Waste and sperms. It opens outside by cloacal aperture.The sperms are passed out through cloacal aperture.