Zoology - Breathing and Exchange of Gases Question with Solution | TestHub

Human respiratory system consists of external nostrils, nasal chamber, pharynx, trachea, bronchi, bronchioles and Lungs. Pharynx opens into trachea through larynx. Trachea is a straight tube in the thoracic cavity and at the level of fifth thoracic vertebra it divides into right and left bronchi which enters the respective Lung. The region at which the division takes place is known as Carina. Primary bronchi when enters the lung further divides into secondary and tertiary bronchi which then forms bronchioles which further extends as alveoli.