ETYM Old Eng. bladder, bleddre, AS. blaedre, blaeddre; akin to Icel. blathra, SW. bläddra, Dan. blaere, Dutch blaar, Old High Germ. blâtara the bladder in the body of animals, German blatter blister, bustule. Related to Blow, to puff.
Hollow elastic-walled organ which stores the urine produced in the kidneys. It is present in the urinary systems of some fishes, most amphibians, some reptiles, and all mammals. Urine enters the bladder through two ureters, one leading from each kidney, and leaves it through the urethra.
1. A bag that fills with air.
2. A distensible membranous sac (usually containing liquid or gas); SYN. vesica. + prikaži više

A membranous sac for temporary retention of urine.

An air-filled sac near the spinal column in many fishes that helps maintain buoyancy; SYN. swim bladder.
A sac containing gas and especially air; especially; a hydrostatic organ present in most fishes that serves as an accessory respiratory organ.

Thin-walled, air-filled sac found between the gut and the spine in bony fishes. Air enters the bladder from the gut or from surrounding capillaries (see capillary), and changes of air pressure within the bladder maintain buoyancy whatever the water depth.
In evolutionary terms, the swim bladder of higher fishes is a derivative of the lungs present in all primitive fishes (not just lungfishes). + prikaži više