Physiology 1020 Lecture Notes - Lecture 10: Brainstem, Rubber Band, Tidal Volume
Document Summary
Transport of oxygen from air to blood. Removal of co2 from blood to air. Lungs are located in the thoracic cavity surrounded by the rib cage and diaphragm. Airways consist of nasal cavity and the mouth which join at the pharynx. Branched airway network: trachea bronchi bronchioles alveoli (gas exchange) Pulmonary artery delivers o2 blood to lungs. O2 diffuses into the blood, co2 diffuses out. Pulmonary vein delivers o2 blood back to the left side of the heart. Inside the lungs: alveolar pressure (760 mmhg) Outside the body: atmospheric pressure (760 mmhg) B/w breaths the alveolar and atmospheric pressure are equal. The chest moving in opposite directions cause lower pressure. Transpulmonary pressure=alveolar-intrapleural pressures (+4 mmhg) positive in healthy lungs. Transpulmonary pressure is important because it holds the lungs open. Pneumothorax= lungs collapse because alveolar and intrapleural pressures are the same (transpulmonary pressure= 0) Pneumothorax occurs when the intrapleural space is punctured.