$$\text{Air Flow} = \dfrac{\Delta \text{Pressure}}{\text{Resistance}}$$

Question 1

Which of the following best describes the primary function of the respiratory system?

Accepted Answer

To supply cells with oxygen and remove carbon dioxide as a waste product

Question 2

Gas exchange in the lungs occurs primarily at which structure?

Accepted Answer

Alveoli

Question 3

According to Boyle's Law, what happens to the pressure of a gas if the volume of its container is halved, assuming temperature remains constant?

Accepted Answer

Pressure is doubled

Question 4

Which equation correctly represents the relationship between airflow, pressure, and resistance in the respiratory system?

Accepted Answer

$$	ext{Air Flow} = \dfrac{\Delta 	ext{Pressure}}{	ext{Resistance}}$$

Question 5

Which factor has the greatest effect on airway resistance according to the equation $$	ext{Resistance} = \dfrac{8L\eta}{\pi r^4$}$$?

Accepted Answer

Radius of the airway ($$r)$$

Question 6

A patient with severe asthma experiences bronchoconstriction. Which medication would most effectively reduce airway resistance?

Accepted Answer

Adrenergic agonist (e.g., epinephrine)

Question 7

What is the role of surfactant in the alveoli?

Accepted Answer

It reduces surface tension, preventing alveolar collapse

Question 8

Which of the following would most likely decrease lung compliance?

Accepted Answer

Formation of scar tissue replacing elastin in lung tissue

Question 9

During inspiration, which of the following occurs?

Accepted Answer

Intrapulmonary pressure drops below atmospheric pressure

Question 10

If intrapleural pressure ($$P_{ip}) $$equals atmospheric pressure ($$P_{atm}$$), what is the likely consequence?

Accepted Answer

Lungs collapse (atelectasis)

Question 11

Which of the following best explains why resistance is lowest at the terminal bronchioles?

Accepted Answer

Total cross-sectional area increases dramatically due to branching

Question 12

A premature infant develops infant respiratory distress syndrome. What is the underlying cause?

Accepted Answer

Insufficient surfactant production

Question 13

Which of the following statements about dead space is correct?

Accepted Answer

Alveolar dead space is due to non-functional alveoli

Question 14

During expiration, which of the following occurs?

Accepted Answer

Intrapulmonary pressure rises above atmospheric pressure

Question 15

Which pressure must always remain lower than intrapulmonary pressure to keep the lungs inflated?

Accepted Answer

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

Question 16

A patient suffers a puncture wound to the parietal pleura. What is the most likely immediate effect?

Accepted Answer

Intrapleural pressure equals atmospheric pressure, causing lung collapse

Question 17

Which of the following best describes the relationship between pressure and volume in the lungs during breathing?

Accepted Answer

Pressure and volume are inversely proportional

Question 18

Which of the following is NOT a factor that hinders pulmonary ventilation?

Accepted Answer

Blood viscosity

Question 19

Which respiratory volume is defined as the amount of air remaining in the lungs after a maximal exhalation?

Accepted Answer

Residual volume

Question 20

A patient with bronchitis has decreased lung compliance. Which of the following is most likely to occur?

Accepted Answer

Breathing requires more muscular effort

Mechanics of Respiration: Ventilation, Pressures, and Lung Volumes

Study Guide - Practice Questions