The respiratory system supplies the blood with oxygen in order for the blood to deliver oxygen to all parts of the body. This specific system is achieved through your mouth, nose, trachea, lungs, and diaphragm. It is located in your head, neck, and chest. In the respiratory system oxygen enters through the mouth or nose. The oxygen then passes through the larynx and the trachea (which is the tube that enters the chest cavity) In the chest cavity, the trachea will split into two smaller tubes called the bronchial. These two tubes will then go to the lungs allowing carbon dioxide to leave and oxygen to enter .

If we happen to not have the respiratory system we wouldn’t be able to get carbon dioxide out, much less get oxygen in. ;-;

the lungs are the main organs in the respiratory system. in the lungs, oxygen is taken into the lungs and carbon dioxide is pushed out.
have you ever wondered why you yawn? well, that is because when you're sleepy or drousy the respiratory system doesn't take in enough oxygen. the brain sences this lack of air and this causes you to take in a deep long breath. a yawn.