Final answer:
During inspiration, extra-alveolar resistance increases while alveolar resistance decreases. Correct option is 2.
Step-by-step explanation:
During inspiration, extra-alveolar resistance increases, while alveolar resistance decreases.
Extra-alveolar resistance refers to the resistance encountered in the larger airways outside the alveoli, such as the trachea and bronchi. During inspiration, the expansion of the thoracic cage and the contraction of the diaphragm decrease the resistance in these larger airways, allowing air to flow more easily.
On the other hand, alveolar resistance refers to the resistance encountered in the smaller airways, specifically the alveoli. During inspiration, the expansion of the alveoli decreases their resistance, facilitating the entry of air into the lungs.