ANATOMY

Detailed explanation-1: -Passing your urine happens when the brain tells the bladder muscle to tighten. This squeezes urine from the bladder. The brain then tells the sphincter muscles surrounding the urethra to relax. This lets the flow of urine go through the urethra and out of the body.

Detailed explanation-2: -Micturition, or urination, is the act of emptying the bladder. When the bladder is full of urine, stretch receptors in the bladder wall trigger the micturition reflex.

Detailed explanation-3: -The bladder never empties completely so some residue is normal. You may find it difficult to start to pass water and that even when you have started; the flow is weak and slow. You might find that you dribble after you have finished passing water. Perhaps you dribble urine all the time, even without noticing.