In this article we will discuss about the structure of respiratory tract of humans with the help of suitable diagram. Also learn about its functions. i. Upper respiratory tract extends from the upper nares to the vocal cord. (Fig. 8.1) ii. Lower respiratory tract extends from the vocal cord to the alveoli. Trachea: The trachea (windpipe) is a cartilaginous and [...]
The air as it enters the lungs meets with two types of resistances: 1. Elastic Resistance 2. Non-Elastic Resistance. Type # 1. Elastic Resistance: Elastic resistance is exerted by the elastic tissue of the lung parenchyma and surface tension of intra-alveolar fluid. Elastic tissues of the lungs obey Hooke's law which means that change in volume of lungs is directly [...]
The expansion of the lungs during inspiration follows the enlargement of the thoracic cavity in all its diameters by the contraction of the respiratory muscles. These are mentioned below: 1. Diaphragm: A dome-shaped muscle separating the abdominal wall from the thoracic cavity, with vertically running fibres at the periphery and horizontally running fibres at the centre ending in the central [...]