The primary function of the respiratory system is to provide oxygen to every part of the body through the process of inhaling oxygen and exhaling carbon dioxide. The respiratory system consists of tissues and organs inside the body that allow people to breathe. This system includes blood vessels, the lungs, airways and certain muscles. The major airways of the respiratory system include the nose, windpipe, mouth, bronchial tubes and larynx.
In the respiratory system, the airways are connected to the lungs, muscles and blood vessels. The respiratory system works by breathing in air through the nose or mouth. Abdominal muscles and the diaphragm help the lungs expand and contract when the body needs to inhale or exhale. After inhaling, air passes through the larynx, travels down the windpipe, goes through the bronchial tubes and enters the lungs. From the lungs, oxygen travels to the veins and arteries. When the body exhales, carbon dioxide exits the body through the windpipe and the nose or the mouth.
In the lungs, small mucus-covered hairs, known as cilia, catch particles and germs. These hairs help filter the air entering the body. Coughing or sneezing is a bodily function that pushes particles or germs out of the body.