How does your body know when to breathe?

Your brain is the part of your body who get signals. The signals will be from your body, and your body will tell the brain how much oxygen and carbon dioxide is in your blood. From here, your brain will know exactly how much Carbon dioxide and oxygen is in your blood. So, the brain will take this piece of information and send it to the muscles involved in breathing.

Your brain is continuously receiving signals from your body that detect the oxygen and carbon dioxide in your blood. Depending on how active you are, the brain can transmit signals to the muscles involved in breathing and change the respiration rate.