Assistant principals aid the principal in the overall administration of the school. Some assistant principals hold this position for several years to prepare for advancement to principal jobs; others are career assistant principals.n larger school systems, a principal is often assisted by someone known as a vice-principal (Republic of Ireland: deputy principal) or assistant principal.
Causes. Pressure on the bladder during delivery is the main cause of a ruptured bladder, although a weakness in the bladder wall may make it susceptible to a rupture. In older horses, a ruptured bladder may be caused by an accident or related to a urinary obstruction.
Overactive Bladder Causes. The urinary bladder is comprised of nerves, muscles, and connective tissue. The most important muscle in the bladder is the detrusor muscle. In normal circumstances, when the bladder fills with urine, it can stretch to hold the urine.When the volume in the bladder reaches close to 300 cc, the stretch in the wall of the bladder can trigger a nerve response to initiate urination (micturition).he urinary bladder is comprised of nerves, muscles, and connective tissue. The most important muscle in the bladder is the detrusor muscle.