Question 1

Which of the following best describes the primary function of the respiratory zone in the lungs?

Accepted Answer

Site of gas exchange between air and pulmonary capillaries

Question 2

A patient with asthma experiences bronchoconstriction. Which of the following best explains the physiological consequence of this event?

Accepted Answer

Increased airway resistance and decreased airflow

Question 3

Which cell type in the alveoli is primarily responsible for secreting pulmonary surfactant?

Accepted Answer

Type II alveolar cells

Question 4

Boyle’s Law is fundamental to pulmonary ventilation. Which equation correctly represents Boyle’s Law?

Accepted Answer

$$P_1V_1 = P_2V_2$$

Question 5

During inspiration, contraction of the diaphragm leads to which of the following changes in intrapulmonary pressure ($$P_{pul}) $$and lung volume ($$V_{pul}$$)?

Accepted Answer

$$P_{pul}$$ decreases, $$V_{pul}$$ increases

Question 6

Which of the following best explains why the intrapleural pressure ($$P_{ip}) is $$always negative under normal conditions?

Accepted Answer

It results from opposing forces of lung recoil and chest wall expansion

Question 7

A newborn with insufficient surfactant production is at risk for which of the following complications?

Accepted Answer

Alveolar collapse due to increased surface tension

Question 8

Which of the following is NOT a function of the conducting zone of the respiratory system?

Accepted Answer

Gas exchange with pulmonary capillaries

Question 9

Which equation describes the chemical reaction that occurs when CO$$_2 is $$transported in the blood and regulated by ventilation?

Accepted Answer

$$CO_2 + H_2O$$ \rightleftharpoons H_2CO_3 \rightleftharpoons $$HCO_3^- + H$$^+$$

Question 10

Which of the following best describes the role of central chemoreceptors in the regulation of ventilation?

Accepted Answer

They respond to rising arterial PCO$$_2 by $$increasing ventilation

Question 11

A patient with asbestosis shows decreased lung compliance. Which of the following best explains the physiological impact of this condition?

Accepted Answer

It becomes more difficult to expand the lungs, reducing ventilation efficiency

Question 12

Which of the following structures marks the transition from the conducting zone to the respiratory zone in the lungs?

Accepted Answer

Respiratory bronchioles

Question 13

Which of the following statements about airway resistance is correct in a healthy individual?

Accepted Answer

Airway resistance is physiologically insignificant due to large lumen and branching

Question 14

Which of the following best describes the function of resident macrophages in the alveoli?

Accepted Answer

Remove debris and pathogens to keep alveolar surfaces sterile

Question 15

Which of the following events occurs during expiration after the diaphragm relaxes?

Accepted Answer

Chest volume decreases and intrapulmonary pressure increases

Question 16

Which of the following is a direct effect of pulmonary surfactant on alveolar function?

Accepted Answer

Decreases surface tension, preventing alveolar collapse

Question 17

Which of the following best explains why gas exchange across the respiratory membrane does not require energy?

Accepted Answer

It occurs via simple diffusion down partial pressure gradients

Question 18

Which of the following is the most potent stimulus for increasing ventilation under normal physiological conditions?

Accepted Answer

Rising arterial PCO$$_2$$

Question 19

Which of the following best describes the role of the VRG (ventral respiratory group) in the medulla?

Accepted Answer

It signals intercostal and phrenic nerves to regulate breathing

Question 20

A patient is exposed to an allergen and develops bronchospasms. Which of the following best explains the mechanism behind the increased airway resistance?

Accepted Answer

Bronchoconstriction due to histamine release

Study Notes: The Respiratory System

Study Guide - Practice Questions

Study Guide - Flashcards