Respiratory — MCQs

A 57-year-old man presents to the clinic for a chronic cough over the past 4 months. The patient reports a productive yellow/green cough that is worse at night. He denies any significant precipitating event prior to his symptoms. He denies fever, chest pain, palpitations, weight changes, or abdominal pain, but endorses some difficulty breathing that waxes and wanes. He denies alcohol usage but endorses a 35 pack-year smoking history. A physical examination demonstrates mild wheezes, bibasilar crackles, and mild clubbing of his fingertips. A pulmonary function test is subsequently ordered, and partial results are shown below: Tidal volume: 500 mL Residual volume: 1700 mL Expiratory reserve volume: 1500 mL Inspiratory reserve volume: 3000 mL What is the functional residual capacity of this patient?

An investigator is studying the clearance of respiratory particles in healthy non-smokers. An aerosol containing radio-labeled particles that are small enough to reach the alveoli is administered to the subjects via a non-rebreather mask. A gamma scanner is then used to evaluate the rate of particle clearance from the lungs. The primary mechanism of particle clearance most likely involves which of the following cell types?

A 22-year-old female is brought to the emergency department by her friends. She was supposed to attend her first job interview in a few hours when she started having palpitations. Her past medical history is insignificant, and she currently takes no medications. Her vitals show the following: pulse rate is 90/min, respiratory rate is 28/min, and blood pressure is 136/86 mm Hg. Her ECG is normal. What will be the patient’s approximate alveolar carbon dioxide pressure (PACO2) given her normal respiratory rate is 14/min and PACO2 is 36 mm Hg? Ignore dead space and assume carbon dioxide production is constant.

A 35-year-old woman volunteers for a study on respiratory physiology. Pressure probes A and B are placed as follows: Probe A: between the parietal and visceral pleura Probe B: within the cavity of an alveolus The probes provide a pressure reading relative to atmospheric pressure. To obtain a baseline reading, she is asked to sit comfortably and breathe normally. Which of the following sets of values will most likely be seen at the end of inspiration?

A 4-month-old boy is brought to the pediatrician for a wellness visit. Upon examination, the physician notes severe burns on the sun-exposed areas of the skin, including the face (especially the ears and nose), dorsal aspect of the hands, shoulders, and dorsal aspect of his feet. The child has very fair skin and blond hair. The parents insist that the child has not spent any extraordinary amount of time in the sun, but they admit that they rarely apply sunscreen. Which of the following physical factors is the most likely etiology for the burns?

A 55-year-old man with a 60 pack-year smoking history is referred by his primary care physician for a pulmonary function test (PFT). A previously obtained chest x-ray is shown below. Which of the following will most likely appear in his PFT report?

A researcher is studying proteins that contribute to intestinal epithelial permeability. He has isolated intestinal tissue from several mice. After processing the tissue into its individual components, he uses a Western blot analysis to identify a protein that forms part of a multi-protein complex at the apical aspect of epithelial cells. The complex is known to provide a diffusion barrier between the apical and basolateral aspects of epithelial cells. Which of the following proteins is this researcher most likely investigating?