Respiratory System Flashcards
What are the functions of the respiratory system?
Gas exchange, olfaction, acid-base balance, blood pressure regulation. blood and lymph flow, platelet production, blood filtration, expulsion of abdominal content
What are the principal organs of the respiratory system?
Nose, pharynx, larynx, trachea, bronchi, lungs.
What is the conducting zone of the respiratory system?
Include passages that serve only for airflow; nostrils through major bronchioles.
What is the respiratory zone of the respiratory system?
Consists of alveoli and other gas exchange regions.
What is the path of airflow?
nasal cavity → pharynx → trachea → main bronchus → lobar bronchus → segmental bronchus → bronchiole → terminal bronchiole → respiratory bronchiole → alveolar duct → atrium → alveolus
Describe the trachea.
Anterior to the esophagus; Supported by hyaline cartilage; Lines by pseudostratified columnar epithelium; Mucous-secreting goblet cells.
Describe the bronchi.
Lined by pseudostratified columnar epithelium; Mucous-secreting; smooth muscle layer to constrict or dilate the airway.
Describe bronchioles.
Ciliates cuboidal epithelium; smooth muscle
Describe the structure of pulmonary alveoli.
Squamous alveolar covers 95% of alveolar surface area; Great (type ll) alveolar cells cover 5% of alveolar surface area - secrete surfactant; Alveolar macrophages (dust cells) are most numerous in lungs. The thin epithelium allows for rapid gas diffusion between air and blood?
Why is it important there is no fluid in the lungs? How do they stay dry?
Gasses would diffuse too slowly to aerate blood. To prevent fluid accumulation, alveoli are kept dry by low pressure in arteriole end capillaries - 10 mm Hg
Describe lung drainage.
Lungs have more extensive lymphatic drainage than any other organ in the body.
Describe the respiratory membrane.
The barrier between the alveolar air and blood, consists only of the squamous alveolar cell, the squamous endothelial cell of the capillary, and their shared basement membrane. These have a total thickness of only 0.5 um, just 1/15 the diameter of a single erythrocyte.
What is the pleura?
A serous membrane that lines the thoracic wall and forms the surface of the lung.
Describe the layers of the pleura.
The visceral layers form the surface of the lungs and extend into the fissures between the lobes. The parietal pleura adheres to the mediastinum, the inner surface of the rib cage, and the superior surface of the diaphragm.
What is the pleural cavity?
The space between the parietal and visceral pleurae. The pleural cavity contains nothing but a thin film of lubricating pleural fluid; the cavity is only a potential space, meaning there is normally no room between the membranes.