lecture exam 3 Flashcards
(75 cards)
What are the four functional processes performed by the respiratory system?
Pulmonary ventilation: movement of gases in and out of lungs. External respiration: gas exchange between lungs and blood. Transport gases within blood. Internal respiration: gas exchange between blood and body tissues.
Why do most inspired fine particles fail to reach the lungs?
Mucous membranes in the oral and nasal cavity, in addition to cilia and mucous in the trachea.
Trace the route of air flow in the respiratory tract from the pharynx to the alveoli.
Pharynx → larynx → trachea → primary bronchus → secondary bronchus → tertiary bronchus → bronchioles, ending in terminal bronchiole → respiratory bronchioles → alveolar duct → alveoli.
The __ consists of mucous membranes supported by the turbinate bones.
nasal cavity
What anatomical structures make up the larynx?
Epiglottis is cartilage that covers the trachea while swallowing. Structural cartilages of larynx include: thyroid, cricoid, arytenoid, and corniculate.
Vestibular folds (false vocal cords) assist in Valsalva’s maneuver, and true vocal folds vibrate to produce sound.
What anatomical structures maintain the openness of the trachea?
Rigid, stacked cartilage rings.
The walls of the alveoli are composed of two types of cells, type I and type II. What is the function of both cell types?
Type I alveolar cells allow for gas exchange, and type II alveolar cells secrete surfactant to reduce surface tension.
Where in the bronchial tree do we have the greatest surface area for gas exchange?
alveoli
What layers make up the respiratory membrane?
Alveolar wall and capillary wall
What does the surface tension from pleural fluid and negative pressure in the pleural cavity contribute to the lungs within the thoracic cavity?
Allows oxygen to diffuse more easily.
Define intrapulmonary pressure?
Pressure within alveoli (lungs).
Define each of the following gas laws: Boyle’s law, Dalton’s law, Henry’s law, Charles’ law. Describe how each of the gas laws relate to pulmonary ventilation.
Boyle’s law: inverse relationship between pressure and volume. Dalton’s law: partial pressures of gases in a mixture equals the total pressure of the mixture. Henry’s law: when a gas comes into contact with a liquid, the gas will dissolve in the liquid in proportion to its partial pressure. Charles’ law: the volume of a gas is proportional to the temperature.
Air moves __ he lungs when the pressure inside the lungs is less than atmospheric pressure. Then, air
moves __ of the lungs when the pressure inside the lungs is greater than atmospheric pressure.
into, out
Which respiratory-associated muscles would contract if you were to forcefully expire?
Mostly internal intercostals, plus other abdominal muscles.
Surfactant helps to prevent the alveoli from collapsing by
reducing surface tension.
What is lung compliance? What factors influence lung compliance?
Lung compliance is the ability of our lungs to expand. Factors that influence it include elasticity of lung tissue, amount of surface tension, and whether there are any degenerative lung diseases present.
Tidal volume (TV)
amount of air inspired during normal, relaxed breathing; ~500mL.
Inspiratory reserve volume (IRV):
additional air that can be forcibly inhaled after tidal inspiration; ~2100-3200mL.
Expiratory reserve volume (ERV)
additional air that can be forcibly
exhaled after tidal exhalation; ~1200mL.
Residual volume (RV)
volume of air remaining in lungs after
ERV is exhaled; ~1200mL.
Inspiratory capacity (IC):
maximum amount of air that can be inspired after tidal expiration; ~3600mL; IC=TV+IRV.
Functional residual capacity (FRC):
total amount of air remaining
2 in lungs after tidal expiration; ~2400mL; FRC=RV+ERV.
Vital capacity (VC):
total amount of air that can be expired after fully inhaling; ~4800mL; VC=TV+IRV+ERV.
Total lung capacity (TLC)
total amount of air that can fill lungs; ~6000mL; TLC=TV+IRV+ERV+RV.