肾是如何工作的？ How do your kidneys work？

It's a hot day,

and you've just downed several glasses of water,

one after the other.

Behind the sudden urge that follows are two bean-shaped organs

that work as fine-tuned internal sensors.

They balance the amount of fluid in your body,

detect waste in your blood,

and know when to release the vitamins, minerals,

and hormones you need to stay alive.

Say hello to your kidneys.