As the number 3 phrase I use, discussing "number 1" seems like a great idea.
Here is your urinary system, in all its glory: kidneys, ureters, bladder, and urethra.
The length of the urethra differs, depending on which
pee-extension hardware you have purchased with your kit.
The urinary system has quite an important job: it's in charge of filtering the blood, removing waste products, and getting these wastes out of the body without harming us.
The basic ingredients of pee are water, urea, and salts.
The lovely yellowish glow of urine is due to urobilin, a byproduct of breaking down hemoglobin from old blood cells--similar to the bilirubin that makes poop brown.
Urea is an easily disposable form of nitrogen. Nitrogen is a tricky element to get rid of, because waste products with nitrogen tend to form ammonia, which is good for cleaning windows, but is poisonous for our bodies. We convert nitrogenous wastes to a urea, which is far less toxic and can be diluted in water and safely removed from our bodies.
So from the kidneys, water and wastes go through the ureters and begin to accumulate in the bladder. When the weight of the pee pool is great enough, you become aware that it's time to evacuate. You engage your bladder muscles while releasing the sphincter that normally pinches your urethra closed, and then you feel that most fabulous of sensations--the bliss that is a good pee.