Here are some facts about the respiratory system, which is the group of tissues and organs in your body that enable you to breathe.

The respiratory system includes:

  • The airways - nose, mouth, voice box (larynx), trachea (windpipe) and bronchial tubes
  • The lungs and their blood vessels
  • The muscles that help you breathe - including but not limited to the diaphragm and intercostal, abdominal and neck muscles

The airways carry air filled with oxygen into your lungs and carbon dioxide (a waste gas) out of them. Your nose and mouth wet and warm the air when they inhale it so it won't irritate your lungs. Cilia (tiny mucous-covered hairs) in your airways entrap foreign particles and germs, which you then cough or sneeze out of your body. The epiglottis, a thin flap of tissue, covers your windpipe so food and drink don't enter your air passages and lead to your lungs when you swallow. It opens again when you breathe.

In order to allow room for your heart, your left lung is a little bit smaller than your right lung. Your lungs have five separate lobes. If for some reason (such as an injury or a disease) you need to have a lobe removed, you'll still be able to breathe fine with your remaining lobes. The bronchial tubes or bronchii, which are inside your lungs, branch into smaller tubes called bronchioles. These end in alveoli, bunches of tiny air sacs covered in capillaries, a mesh of blood vessels that connect to the veins and arteries that carry your blood throughout your body. The muscles around your lungs help them expand and contract so you can breathe. The muscles in your neck and around your collarbone are generally used to help you breathe when the function of the other muscles is impaired for some reason.