NATS 4210 Lecture Notes - Lecture 8: External Intercostal Muscles, Thoracic Cavity, Alveolar Pressure
14 Dec 2016
School
Department
Course
Professor
Document Summary
Ventilation forced flow of air or water into and out of structures used for external respiration or over body surfaces used for respiration. Pulmonary ventilation ( breathing ) - flow of air into (inhalation) and out (exhalation) of lungs. External respiration - gas exchange between alveoli and blood in pulmonary capillaries; exchanging with the external environment: oxygen diffuses from alveoli to blood and carbon dioxide diffuses from blood to alveoli. Internal respiration - gas exchange between tissue cells and blood in systemic capillaries; exchanges within the internal body environment: oxygen diffuses from blood into tissues, while carbon dioxide diffuses into blood from tissues. Alveoli - have a large surface area and a short diffusion distance, both of which increase the rate of gas exchange. Alveolar cell (type 1) thin-walled, squamous epithelial cell that is the site of gas exchange. Alveolar cell type 2 secretes surfactant. Alveolar macrophage remove dust and debris from alveolar spaces.
