Bladder pipe

Okay, so imagine a tube that goes from your bladder (where you hold pee) to outside your body where you pee. This tube is called the bladder pipe, or urethra. Boys and girls both have bladder pipes, but boys' are longer because they need to go through their penis. When you need to pee, your bladder squeezes and pushes the pee out through the bladder pipe. It's important to make sure you always try to go to the bathroom when you need to, so your bladder doesn't get too full and make you uncomfortable.