Question 1

Which of the following best describes the function of surfactant in the alveoli?

Accepted Answer

It decreases the surface tension of alveolar fluid, preventing collapse.

Question 2

A patient with left-sided heart failure develops pulmonary edema. Which of the following best explains why gas exchange is impaired in this condition?

Accepted Answer

The respiratory membrane thickens, increasing the distance for gas diffusion.

Question 3

According to Boyle’s Law, what happens to the pressure in the lungs if the volume of the thoracic cavity increases during inspiration?

Accepted Answer

Pressure decreases, causing air to flow into the lungs.

Question 4

Which structure prevents food from entering the lower respiratory tract during swallowing?

Accepted Answer

Epiglottis

Question 5

A 3-year-old aspirates a peanut. Which main bronchus is most likely involved and why?

Accepted Answer

Right main bronchus, because it is wider and more vertical.

Question 6

Which of the following equations correctly represents Dalton’s Law of Partial Pressures?

Accepted Answer

$$P_{total} = P_1$ + P_2$ + P_3$ + \ldots + P_n$$

Question 7

A patient presents with rapid breathing, a blood $$PCO_2 of 26 $$mmHg, and a blood pH of 7.5. What is the most likely diagnosis?

Accepted Answer

Respiratory alkalosis due to hyperventilation

Question 8

Which of the following would shift the oxygen-hemoglobin dissociation curve to the right?

Accepted Answer

Increased $$CO_2$$ concentration

Question 9

How is the majority of $$CO_2$$ transported in the blood?

Accepted Answer

As bicarbonate ion ($$HCO_3$$^-$$) in plasma

Question 10

Which of the following best describes the difference between obstructive and restrictive pulmonary diseases as measured by spirometry?

Accepted Answer

Obstructive diseases show reduced FEV1/FVC ratio; restrictive diseases show reduced total FVC but normal or near-normal FEV1/FVC ratio.

Question 11

Which of the following is a function of the nasal cavity?

Accepted Answer

Filtering, warming, and moistening incoming air

Question 12

Which pressure is always negative under normal conditions and helps keep the lungs inflated?

Accepted Answer

Intrapleural pressure ($$P_{ip})$$

Question 13

A patient with carbon monoxide poisoning has a left-shifted oxygen-hemoglobin dissociation curve. What is the physiological consequence?

Accepted Answer

Oxygen is not released efficiently at the tissues.

Question 14

Which of the following best explains why slow, deep breaths ventilate the alveoli more effectively than rapid, shallow breaths?

Accepted Answer

They allow more fresh air to reach the alveoli, reducing the proportion lost to dead space.

Question 15

Which of the following is NOT a function of the larynx?

Accepted Answer

Gas exchange

Question 16

Which of the following best describes the effect of increased airway resistance, as seen in asthma, on pulmonary ventilation?

Accepted Answer

It decreases airflow, making expiration more difficult.

Question 17

Which of the following best describes the role of the pleurae in lung function?

Accepted Answer

They produce lubricating fluid and compartmentalize the lungs.

Question 18

A patient with a puncture wound to the chest develops a pneumothorax. Which of the following best explains why the lung collapses?

Accepted Answer

The intrapleural pressure becomes equal to atmospheric pressure, eliminating the transpulmonary pressure.

Question 19

Which of the following best describes the primary drive to breathe under normal conditions?

Accepted Answer

High blood carbon dioxide levels

Question 20

Which of the following is the correct formula for calculating the total pressure of a gas mixture according to Dalton’s Law?

Accepted Answer

$$P_{total} = P_1$ + P_2$ + P_3$ + \ldots + P_n$$

Chapter 22: The Respiratory System – Structure, Function, and Clinical Concepts

Guida di studio - Domande di pratica

Study guide - Flashcard