To pee or not to pee, that is the question.
[TOILET FLUSHING] And if you think you're in charge of the answer, think again.
Peeing may seem simple,
but it's actually a complex process coordinated by your central nervous system.
As your kidneys produce urine, your bladder slowly fills up.
[STRETCHING NOISE] Layers of muscle stretch so it can expand,
while circular muscles keep pee from leaking out.
As your bladder reaches maximum capacity,
nerves send messages to your spinal cord that the pressure is building.
Those signals then travel to different parts of the brain
asking for, well, permission to pee.
If it's not a good time to go,
your brain tells those muscles to [SLAM] stay shut.
But if the time is right,[BELL]
it tells your sphincter muscles to loosen up and your bladder to contract.
The urethra then opens, [WATER FLOWING] and urine flows out.
[CHEERING] So relax. When it comes to peeing,
your bladder and your brain have it all under control. [WHISTLING]