ELI5: Explain Like I'm 5

Physiology

Physiology is the study of how your body works. It's like a big puzzle, and when all the pieces come together correctly, you're healthy and can do the things you want to do. For example, muscles, bones, and brains all work together to help you run, jump, and play. Your heart and lungs work together to get oxygen to all parts of your body, and your skin helps keep all your body parts safe from the outside world. Physiology helps us understand why some things can make us feel better, like eating healthy food and drinking water, and why other things can make us feel worse, like smoking cigarettes.