Urinogenital System of Frog | Zoology : Biology

UNIT SEVEN | DETAILED STUDY OF FROG
Class 11

Urinogenital System of frog

The excretory and reproductive systems are functionally unrelated but products of these two systems have common passage. In frog the sexes are separate hence it can be studied under two headings Male and female reproductive system. 

Male reproductive system 

It consists of a pair of testes, vasa efferentia, bidder’s canal, transverse collecting tubules, urinogenital ducts, and cloaca. 

Testes : Testes are elongated or oval, light yellow, is found attached to the anterior ventral side of each kidney to which they are suspended by a double fold of peritoneum called Mesorchium. Each testes consists coiled structures called seminiferous tubules. The epithelial lining of seminiferous tubules consists of germinal cells, which produce spermatozoa. Many seminiferous tubules unite to form vasa efferentia, which is narrow tube like structure.  The vasa efferentia runs through kidney and open into the Bidder’s canal, which is then connected to the ureter. The sperms pass through vasa efferentia, bidder’s canal, ureter and cloaca.  The urine and sperms pass through ureter so that it is also called as urinogenital duct. Each urinogenital duct expands to form seminal vesicle where the sperms are stored until they are ejected out during copulation 

Female urinogenital system 

It consists of ovaries, oviducts, ovisacs and coaca. 

Ovary 

Each ovary lies like testes on ventral to the kidneys and hang in loops of peritoneum called mesovarium. It is lobulated sac like structures composed of ovarian follicles consists of countless ova. Ova are produced by oogenesis from epithelial cells of ovary. The mature ova are shed into the abdominal cavity and reach to the oestium by pressure of fore arms of clasping of male. 

Oviduct 

Long coiled glandular tubes one on either side of abdominal cavity. Anterior of oviducts oviducal funnel or ostium is present. The posterior of oviducts swollen ovisacs where the ova are stored temporarily are present. Oviducts open into the cloaca. The inner wall of oviducts is ciliated.