Hi Students,
In this blog, we are going to learn about anatomy of respiratory system. Respiratory system in human beings includes all those organs which in coordination with each other achieve a single objective “exchange of gases”.
Before proceeding to study anatomy, it’s important to learn the meaning of exchange of gases. Our body needs oxygen which breakdown glucose into carbon dioxide and water to obtain food energy from it. And the carbon dioxide produced in the process needs to be expelled from the body as it turns toxic if gets accumulated inside body. Respiratory system provides a single location where absorption of oxygen and expulsion of carbon dioxide takes place.
Respiratory system of human beings is categorized into upper respiratory tract and lower respiratory tract. As can be seen in the diagram below the upper respiratory tract includes a pair of opening of nose called nostrils followed by nasal cavity, Pharynx and Larynx, the lower respiratory tract consists of Trachea (wind pipe) which splits into two branches – right bronchi and left bronchi – which enter into lungs. Inside lungs bronchi further split into smaller branches called bronchioles which eventually end into small sac like microscopic structure called Alveoli.
Alveoli is the actual structure where the exchange of gases take place. each Alveoli is surrounded by blood capillaries that contain the deoxygenated blood received from heart. when we inhale the air it ultimately reaches out to alveoli. the blood in the surrounding capillaries is rich in carbon dioxide.
following pressure and concentration gradients, the oxygen diffuses into the blood capillaries where the carbon dioxide diffuses into alveoli from blood vessels. From alveoli, the carbon dioxide is exhaled out of the body whereas the oxygen in the blood is taken to heart where it is distributed to the entire body tissues.
