SUBPHYLUM VERTEBRATA 



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The kidneys serve for the eUmination of Uquid waste which contains the 

 end products of metaboUsm. The ducts connected directly to the 

 kidneys are known as ureters; they meet to form the urethra. Where 





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they meet, a bladder may be developed in which the urine is stored before 

 being passed out of the body. 



There are three types of kidneys in the vertebrates, all similar in 

 plan, which involves a series of nephridial tubules metamerically arranged 



