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URINARY SYSTEM IN TETRAPODS

SALAMANDER

SALAMANDER

SALAMANDER

FROG

FROG

FROG
FROG

TURTLE

TURTLE

ALLIGATOR

ALLIGATOR

OPOSSUM

OPOSSUM

OPOSSUM
OPOSSUM

COW

COW

SHEEP

SHEEP

SHEEP
SHEEP

GOAT

GOAT

GOAT

PIG

URINARY SYSTEM

KIDNEY

 

URINARY SYSTEM
KIDNEY

CAT

CAT

CAT
CAT CAT
CAT

MONKEY

MONKEY

MONKEY

HUMAN MODELS

HUMAN MODEL

HUMAN MODEL

URETERS, BLADDER, AND URETHRA

While cartilaginous fish possess a bladder in females only, this structure for the storage of urine is present in both genders of most higher vertebrates (Romer, p. 416).  The urinary bladder in many reptiles develops from the cloaca and the base of the allantois.  Crocodiles lack urinary bladders, as to birds (with the sole exception of the ostrich)  (Weichert, 1970, p. 265).

     In monotremes, the ureters open into the urethra near the base of the bladder; in other mammals they empty into the superior portions of the bladder. (Weichert, 1970, p.269)  In the females of most primates and many rodents, the urinary and reproductive systems are separate. (Weichert, 1970, 270)

Transitional Epithelium lining the Bladder in a Frog

BLADDER