Structures of the respiratory system Respiratory structures in the head and neck, Anterolateral view of external portion of nose showing cartilaginous and bony framework Respiratory structures in the head and neck, Sagittal section of the left side of the head and neck showing the location of respiratory structures (Part 1) Respiratory structures in the head and neck, Sagittal section of the left side of the head and neck showing the location of respiratory structures (Part 2) Pharynx, Sagittal section of the regions of the pharynx Larynx, Anterior View, Posterior View Larynx, Sagittal section Branching of airways from the trachea; the bronchial tree Surface anatomy of the lungs, Medial view Surface anatomy of the lungs, Lateral view Microscopic anatomy of a lobule of the lungs, Diagram of a portion of a lobule of the lung Structural components and function of an alveolus, Transverse section of an alveolus showing its cellular components