Overview Extent of Lungs apex is located above the clavicle base rests on the diaphragm Right Lung 3 lobes upper (superior), middle, and lower (inferior) lobes 2 fissures oblique (major) fissure separates upper and lower lobes horizontal (transverse) fissure separates upper and middle lobes Left Lung 2 lobes upper (superior) and lower (inferior) lobes 1 fissure oblique fissure cardiac notch an indentation consequent to the deviation of apex of heart to left side lingula is a flap of lung tissue of the left upper (superior) lobe that lies below cardiac notch homolog of right middle lobe the apex of the heart is covered anteriorly by the left lung lies at the left fifth intercostal space at the midclavicular line Hilum of Lung a wedge-shaped area on mediastinal surface of each lung through which structures forming root of lung pass to enter or to exit lung Relationship of pulmonary artery (PA) to bronchus ("RALS") right lung: anterior to bronchus left lung: superior to bronchus Trachea bifurcates into left and right (primary) main bronchi at level of sternal angle right (primary) main bronchus is shorter, wider, and runs more vertically foreign body is more likely to pass through right (primary) main bronchus and into right lung upright position inferior (basal) portion of right lower (inferior) lobe supine position posterior portion of the right upper lobe superior portion of right lower (inferior) lobe