Question

Describe the journey of an oxygen molecule through our body.

Answer 1

The Respiratory System begins at the nose.  You inhale the oxygen here.  The air then travels into the pharynx, or throat.  In addition to air, food and drink also travel through the pharynx.  Therefore, the pharynx is part of both the Respiratory and Digestive Systems.  It branches into two tubes: one leads to the stomach, and the other to the lungs.

After that, the air travels into the larynx, or voice box.  The larynx controls your vocal cords, which allow you to speak and communicate with voice.  If you rub a finger up and down the front of your throat, the ridges you feel are the outside of the larynx.

The oxygen now travels into the trachea, or windpipe.  The trachea is the passegeway for air traveling from the larynx to the lungs.  After that, the air travels to the bronchi.  The trachea splits into two tubes called the bronchi.  One tube goes to each lung and branches into thousands of tiny sacs called bronchioles.

Once the oxygen has traveled through you bronchioles, it enters your lungs.  Your lungs are two sponge-like organs that fill with air when you inhale, and you exhale carbon dioxide.  The contracting and expanding of the lungs is controlled by the diaphragm, the only muscle in the Respiratory System.  The process of breathing is called respiration.

Once inside the lungs, oxgen is forced into little holes called alveoli, which are covered in capilleries that cover them.  The capillaries bring oxygen into the bloodstream, where it is delivered to other bodily systems.