Bounded by the chest wall and below by the diaphragm, it extends upward into the root of the neckabout one fingerbreadth above the clavicle on each side Chest cavity the only structure (apart from the pleura and the peritoneum)that separates the chest from the abdominal viscera Diaphragm a median partition mediastinum a movable partition that extends superiorly to the thoracic outlet and the root of the neck and inferiorly to the diaphragm mediastinum The mediastinum is divided into superior and inferior mediastinum The inferior mediastinum is further subdivided into the ________,which consists of the pericardium and heart; the ________, which is a space between the pericardium and the sternum; and the ________, which lies between the pericardium and the vertebral column middle mediastinum anterior mediastinum posterior mediastinum Consist the superior mediastinum Thymus large veins large arteries trachea esophagus and thoracic duct sympathetic trunks. composes the inferior mediastinum Thymus Heart within the pericardium with the phrenic nerves on each side esophagus and thoracic duct descending aorta sympathetic trunks bounded in front by the manubrium sterni and behind by the first four thoracic vertebrae superior mediastinum bounded in front by the body of the sternum and behind by the lower eight thoracic vertebrae inferior mediastinum 2 parts of a pleura parietal layer mediastinal layer lines the thoracic wall, covers the thoracic surface of the diaphragm and the lateral aspect of the mediastinum parietal layer covers the outer surfaces of the lungs and extends into the depths of the interlobar fissures visceral layer a loose fold that allow for movement of the pulmonary vessels and large bronchi during respiration pulmonary ligament a slit like space that separate he parietal and visceral layers of pleura are from one another pleural cavity/ pleural space covers the surfaces of the pleura as a thin film and permits the two layers to move on each other with the minimum of friction pleural fluid extends up into the neck, lining the under surface of the suprapleural membrane (see Fig. 2.13). It reaches a level 1 to 1.5 in. (2.5 to 4 cm) above the medial third of the clavicle. cervical pleura lines the inner surfaces of the ribs, thecostal cartilages, the intercostal spaces, the sides of the vertebralbodies, and the back of the sternum costal pleura covers the thoracic surface ofthe diaphragm diaphragmatic pleura This lower area of the pleural cavity into which the lung expands on inspiration is referred to as the ________ costodiaphragmatic recess covers and forms the lateral boundary of the mediastinum mediastinal pleura where the mediastinal pleura is attached to the blood vessels and bronchi that constitute the lung root hilum are slitlike spaces between the costal and diaphragmatic parietal pleurae that are separated only by a capillary layer of pleural fluid Costodiaphragmatic Recesses are situated along the  anterior margins of the pleura Costomediastinal Recesses They are slitlike spaces between the costal and mediastinal parietal pleurae, which are separated by a capillary layer of pleural fluid Costomediastinal Recesses The costal pleura is segmentally supplied by what nerve Intercostal nerve The mediastinal pleura is supplied by the Phrenic Nerve The diaphragmatic pleura is supplied over the domes by the _____ and around the periphery by the _____ Phrenic Nerve & Lower intercostal nerves It is insensitive to common sensations such as pain and touch and it receives an autonomic nerve supply from the pulmonary plexus Visceral Pleura It is a mobile cartilaginous and membranous tube and It begins in the neck as a continuation of the larynx at the lower border of the cricoid cartilage at the level of the 6th cervical vertebra trachea In the thorax, the trachea ends below at the _____ by dividing into right and left principal bronchi at the level of the sternal angle carina In adults, the trachea is about _____long and _____ in diameter 4 1/2 in. (11.25cm) & 1 in. (2.5 cm Is kept patent by the presence of U-shaped bars (rings) of hyaline cartilage embedded in its wall Fibroelastic tube The posterior free ends of the cartilage are connected by smooth muscle trachealis muscle The relations of the trachea in the superior mediastinum of the thorax anteriorly: The sternum, the thymus, the left brachiocephalic vein, the origins of the brachiocephalic, left common carotid arteries, the arch of the aorta The relations of the trachea in the superior mediastinum of the thorax posteriorly: The esophagus, the left recurrent laryngeal nerve The relations of the trachea in the superior mediastinum of the thorax right side; The azygos vein, the right vagus nerve, the pleura The relations of the trachea in the superior mediastinum of the thorax left side: The arch of the aorta, the left common carotid, left subclavian arteries,the left vagus and left phrenic nerves, and the pleura The upper two thirds of the trachea are supplied by the inferior thyroid arteries the lower third of the trachea is supplied by the bronchial arteries The sensory nerve supply is from the Vagi and Recurrent laryngeal nerves Sympathetic nerves supply the trachealis muscle The trachea bifurcates behind the arch of the aorta into the right and left principal (primary or main) bronchi Each respiratory bronchiole divides into ______ alveolar ducts that enter the alveolar sacs 2 to 11 The right principal (main) bronchus is wider, shorter, and more vertical and is about 1 in (2.5 cm) long The left principal (main) bronchus is narrower, longer, and more horizontal than the right and is about 2 in. (5 cm) long During life, the right and left lungs are: soft, spongy,\very elastic If the thoracic cavity were opened, the lungs would immediately shrink to one third or less in volume Each lung has a ________, which projects upward into the neck for about 1 in. (2.5 cm) above the clavicle blunt apex Concave base of the lungs sits on the diaphragm Part of the lungs which corresponds to the concave chest wall convex costal surface Part of the lungs which is molded to the pericardium and other mediastinal structures concave mediastinal surface depression in which the bronchi, vessels, and nerves that form the root enter and leave the lung hilum The _______ runs from the inferior border upward and backward across the medial and costal surfaces until it cuts the posterior border about 2.5 in. (6.25 cm)below the apex oblique fissure Runs horizontally across the costal surface at the level of the 4th costal cartilage to meet the oblique fissure in the mid axillary line Horizontal Fissure the anatomic, functional,and surgical units of the lungs Bronchopulmonary segment structurally and functionally independent unit of a lung lobe bronchopulmonary segment smallest bronchi, <1 mm in diameter Bronchioles possess no cartilage in their walls and are lined with columnar ciliated epithelium. The submucosa possesses a complete layer of circularly arranged smooth muscle fibers Bronchioles bronchioles then divide and give rise to terminal bronchioles Gaseous exchange between blood and air takes place in the walls of these outpouchings Respiratory bronchioles main characteristics of a bronchopulmonary segment It is a subdivision of a lung lobe It is pyramid shaped, with its apex toward the lung root It is surrounded by connective tissue It has a segmental bronchus, a segmental artery, lymph vessels, and autonomic nerves The segmental vein lies in the connective tissue between adjacent bronchopulmonary segments Because it is a structural unit, a diseased segment can beremoved surgically formed of structures that are entering or leaving the lung (made up of the bronchi,pulmonary artery and veins, lymph vessels, bronchial vessels, and nerves) root of the lung The bronchi, the connective tissue of the lung, and the visceral pleura receive their blood supply from the bronchial arteries, which are branches of the ________ descending aorta The bronchial veins (which communicate with the pulmonary veins) drain into the ________ azygos and hemiazygos veins lies beneath the visceral pleura and drains over the surface of the lung toward the hilum, where the lymph vessels enter the bronchopulmonary nodes superficial (subpleural) plexus All the lymph from the lung leaves the hilum and drains into the ______ and then into the ______ tracheobronchial nodes & bronchomediastinal lymph trunks Nerve Supply of the Lungs pulmonary plexus