Question

Question 36 5 pts 2 36) Answer both of these questions. a) Describe how humans bring air into their lungs. This answer requires multiple sentences. b) Is this negative or positive pressure breathing? HTML Editor BIU A- A - IX E 1 1 x XE Del 2 VG TT 12pt

Answer 1

a) Humans inhale the oxygen-rich air from the atmosphere through nose or the mouth. The pharynx is located at the back side of the the throat. The inhaled air passes down through pharynx followed by larynx and the windpipe called trachea. The trachea is divided into two tubes called as bronchial tube and each of the bronchial tube is connected to the each of the two lungs. The bronchial tube directs the inhaled air to the lungs.  

b) For the atmospheric air to reach the lungs smoothly there should be a pressure gradient between the lung and the atmosphere. During the process of inhalation, the lung will expand and thus the volume of lungs will also expand leading to the contraction of the diaphragm and the associated muscles. As the volume of the lung increases the pressure is decreased. Because of the low lung pressure as compared to the atmosphere the air enter into the airways. Thus breathing creates negative pressure inside the lungs which allows the air to enter into the lungs from the atmosphere.