Review the anatomical structures that a molecule of O2 would…
Review the anatomical structures that a molecule of O2 would encounter on its journey from the atmosphere to an alveolus by completing each sentence. 1. During inspiration, air passes through either the or mouth into the , a passage common to both air and food. 2. The pharynx branches into two paths: the , through which food passes to the stomach, and the , which is part of the airways and houses the vocal cords. 3. The larynx opens into a long tube, the , which in turn branches into two , one of which enters each lung. Rings of cartilage support the walls. 4. The first airway branches that no longer contain cartilage are termed . 5. Bronchioles continue branching into the , which are the final airways of the zone. This zone contains no and therefore has no gas exchange with the blood. 6. Alveoli first begin to appear attached to the walls of the , which then branch into the esophagusnosealveolar ductsalveolar sacsalveolibronchibronchiolesconductinglarynxpharynxrespiratoryrespiratory bronchiolesterminal bronchiolestrachea, and the airways finally end in grape-like clusters consisting entirely of alveoli, which are called .