urinary bladder

urinary bladder   n.  An elastic, muscular sac situated in the anterior part of the pelvic cavity in which urine collects before excretion.

urinary bladder

A saclike structure that stores urine until it can be passed out of the body through the urethra.

Main Entry: urinary bladder
Function: noun
: a distensible membranous sac that serves for the temporary retention of the urine, is situated in the pelvis in front of therectum, receives the urine from the two ureters and discharges it at intervals into the urethra through an orifice closed by a sphincter, is lined with transitional hypoblastic epithelium, and developsfrom the proximal part of the allantois of the embryo

urinary bladder n.
A musculomembranous elastic receptacle in the anterior part of the pelvic cavity serving as the temporary storage place for urine.

urinary bladder

in most vertebrates, except birds, organ for the temporary storage of urine from the kidneys, connected to the kidneys by means of tubular structures called ureters. A urinary bladder is present in fish as an expansible part of the urinary duct, in amphibians and bladder-possessing reptiles (Sphenodon, turtles, most lizards) as a pocket in the cloaca. In mammals it is a greatly expandible muscular sac. The bladder of an average adult human is uncomfortably distended at a volume of around 350 millilitres (13 quart) of urine.

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