What is the impor

● Trachea is the windpipe of human beings. It is a long tube made up of C-shaped hyaline cartilage that is lined by pseudo stratified ciliated columnar epithelium. Trachea joins larynx with bronchi and take air from neck to chest.

● The trachea gets divided into 2 parts in the chest cavity and enter into the lungs from each side. These parts/ branches are known as primary bronchi which split into secondary bronchi. Secondary bronchi again splits into tertiary bronchi in each part of the lungs. These tertiary bronchi are further split into small bronchioles. The main function of bronchi and bronchiole is to carry air from trachea to the lungs. They have smooth muscle tissues in their walls that help to regulate the air flow into the lungs.

● Lungs are 2 sac like spongy organs that are found in our chest/ thoracic cavity. Left lung consists of 2 lobes while the right lung consists of 3 lobes. The function of lungs is to bring oxygen into the body when we inhale and to remove carbon dioxide from our body when we exhale.

● Air enters into the lungs by contraction of diaphragm and leaves the lungs by relaxation of diaphragm. Respiratory muscles are required for inhaling and exhaling air from the atmosphere. These muscles are found in the lungs. The most important respiratory muscles are the inter costal muscles which are found in sets. The external intercostal muscles that pull the ribs together thus raising the rib cage during inspiration and the internal intercostal muscles which depress the rib cage during expiration.