Components of respiratory function tests

The respiratory system is composed of the lungs, the conducting airways, the parts of the central nervous system concerned with the control of the muscles of respiration, and the chest wall. The main functions of the respiratory system are to obtain oxygen from the external environment and supply it to the cells and to remove from the body the carbon dioxide produced by cellular metabolism. Pulmonary function tests provide valuable clinical information. They are designed to identify and quantify defects in the respiratory system.