ELI5: Glomerulus

A glomerulus is a tiny, ball-shaped filter inside your kidney that cleans your blood by catching trash while keeping the good stuff inside your body.

Think of it like a kitchen strainer you use when cooking pasta:

• The Good Stuff: When you pour cooked spaghetti into a colander, the pasta stays inside because it is too big to fit through the holes. In your body, important things like blood cells and proteins are like the pasta—the glomerulus keeps them safe inside your bloodstream.
• The Waste: The hot water easily slips through the tiny holes in the strainer and goes down the drain. In your body, extra water, chemicals, and waste products pass right through the glomerulus. This liquid eventually turns into your pee.

Every day, while you are playing, eating, and sleeping, your glomeruli work nonstop like tiny washing machines. Without them, bad waste would build up in your body and make you feel very sick, but thanks to these little filters, your blood stays fresh and clean.