Kidney

Kidney explained in an easy to understand way:

Imagine you're cleaning out your refrigerator, trying to separate the expired food from the fresh produce. Just like you sift through the items to discard what's unusable and keep what's good, your kidneys filter your blood to remove waste while retaining essential nutrients. In this analogy, the expired food represents waste products in your blood, and the fresh produce symbolizes the nutrients and water your body needs to keep, illustrating how the kidneys maintain your body's internal environment by filtering out the unwanted substances.