The Respiratory System II Flashcards
Whats the function of a Respiratory Membrane?
Exchange of O2 and CO2 between air spaces in the lungs and the blood
~0.5 m thick air-blood barrier to allow rapid diffusion of gases
How does Voice Production occur?
Vocal folds are adducted (closed), air is exhaled upwards and blows apart the vocal folds setting them into a rapid vibratory pattern
What are the four layers of Trachea?
Mucosa: pseudostratified ciliated columnar epithelium
Submucosa: connective tissue with seromucous glands
Hyaline cartilage: 16-20 incomplete rings (semi rigid support). Posteriorly attached to the esophagus (trachealis muscle, elastic connective).
Adventitia: outermost layer made of connective tissue that encases the C-shaped rings of hyaline cartilage
What structures make the Respiratory zone?
Respiratory bronchioles, alveolar ducts, alveolar sacs (clusters of alveoli)
What structures make the Conduction zone?
Lobule: arteriole, venule, lymphatic vessel, branch from a terminal bronchiole
What are the different cells present in Alveoli?
Type I cells: squamous epithelial cells, continuous lining of the alveolar wall
Type II cells: scattered rounded or cuboidal cells containing microvilli, secrete alveolar fluid (surfactant)
Surfactant: mixture of phospholipids and lipoproteins (lower the tension of alveolar fluid reducing the tendency of alveolar wall to collapse)
Alveolar macrophages (dust cells): remove dust particles and
What is the functional anatomy of the Respiratory system?
Conducting zone: conducts air into the lungs
Respiratory zone: site of gas exchange
Whats Intrapulmonary pressure?
Pressure in the alveoli
Whats Intrapleural pressure?
Pressure in the pleural cavity
3 Physical Factors Influencing Pulmonary Ventilation?
Airway resistance
Alveolar surface tension
Lung compliance
Airway Resistance?
During inspiration bronchioles enlarge resistance decreases
During expiration bronchioles diameter decreases resistance increases
Alveolar Surface Tension?
Force exerted on the thin layer of alveolar fluid caused by the attraction of the molecules beneath
What is Compliance?
Measure of lungs capacity to expand the V as a result of a change in pulmonary P
What is Pulmonary fibrosis?
Reduced compliance
What is Emphysema?
Increased compliance
What is the Control of Respiration?
Respiratory muscles controlled by nerve impulses from respiratory center (involves neurons in the reticular formation of the medulla and pons)
What are the affects of disease on the respiratory system?
Emphysema: alveolar sacs damaged and enlarged
Chronic bronchitis: respiratory passages swollen and irritated. Increase in mucous production
(Smoking)
Oxygen transport through blood?
Only about 1.5% dissolved in plasma
98.5% bound to haemoglobin (Hb) in red blood cells (oxyhaemoglobin)
Heme portion of haemoglobin contains 4 iron atoms – each can bind one O2 molecule
Only dissolved portion can diffuse out of blood into cells
