That is, Anomalocaris has it right as regards the muscularity of the bladder. As a health pro, I’d discourage as a general rule the practice of trying to dilate your own bladder for convenience’s sake. If you really think you’re peeing too often, chat with your doctor first.
Thanks, Quadgop. That explains the difference nicely.
I finally get to use something I learned in my Body Structure & Function class! The bladder wall is made up of 3 layers, one of which is the muscular coat. It is comprised of interlaced coarse bundles of smooth muscle fibers. Together they are the detrusor muscle.The portion of this muscle that surrounds the neck of the bladder forms an internal urethral sphincter, which is controlled by the parasympathetic nervous system; you have no conscious control over this. There is also an external urethral sphincter which is composed of voluntary skeletal muscle; theoretically you should be able to strengthen this muscle. Unfortunately, bladder capacity is dictated by the amount of stretch you have in the bladder’s transitional epithelium, the cells that make up the inner lining of the bladder. The urinary bladder may hold as much as 600 milliliters of urine before stimulating pain receptors, but the urge to urinate usually begins when it contains about 150 milliliters.