$$\text{Alveolar ventilation} = \text{ventilation rate} \times (\text{tidal volume} - \text{dead space volume})$$

$$\text{Flow} = \dfrac{\text{Pressure gradient}}{\text{Resistance}}$$

Question 1

Which of the following is NOT a primary function of the respiratory system?

Accepted Answer

Production of red blood cells

Question 2

Which statement best explains why air flow and blood flow differ in their physical properties?

Accepted Answer

Air is a compressible mixture of gases, while blood is an incompressible liquid

Question 3

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

Accepted Answer

Pressure increases

Question 4

Which equation correctly represents Boyle's Law?

Accepted Answer

$$P_1V_1 = P_2V_2$$

Question 5

A patient has a tidal volume of 500 mL and a ventilation rate of 12 breaths/min. What is their total pulmonary ventilation?

Accepted Answer

$$6\,L/min$$

Question 6

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

Accepted Answer

It decreases surface tension, making alveoli easier to expand

Question 7

Which cell type is responsible for synthesizing surfactant in the alveoli?

Accepted Answer

Type II alveolar cells

Question 8

During quiet breathing, which muscles are primarily responsible for inspiration?

Accepted Answer

Diaphragm, external intercostals, and scalenes

Question 9

Which of the following lung volumes cannot be measured directly by spirometry?

Accepted Answer

Residual volume (RV)

Question 10

What is the correct formula for calculating alveolar ventilation?

Accepted Answer

$$	ext{Alveolar ventilation} = 	ext{ventilation rate} 	imes (	ext{tidal volume} - 	ext{dead space volume})$$

Question 11

Which of the following best describes the relationship between flow, pressure gradient, and resistance in the respiratory system?

Accepted Answer

$$	ext{Flow} = \dfrac{	ext{Pressure gradient}}{	ext{Resistance}}$$

Question 12

Which of the following changes would most likely increase airway resistance?

Accepted Answer

Decreasing the diameter of the bronchioles

Question 13

What is the main reason why premature babies with insufficient surfactant have difficulty breathing?

Accepted Answer

Their alveoli collapse after each exhalation, requiring more effort to expand them

Question 14

Which of the following is a restrictive lung disease?

Accepted Answer

Pulmonary fibrosis

Question 15

What is the effect of increased compliance on lung function?

Accepted Answer

Lungs stretch more easily, requiring less force to expand

Question 16

Which of the following best describes the role of the pleural sac in lung function?

Accepted Answer

It creates a slippery surface for membranes to slide across each other

Question 17

What happens to alveolar pressure during inspiration?

Accepted Answer

It decreases below atmospheric pressure

Question 18

Which of the following is true about the anatomical dead space?

Accepted Answer

It is the volume of air in the conducting airways that does not participate in gas exchange

Question 19

Auscultation is used in clinical practice to:

Accepted Answer

Listen to breath sounds and diagnose pulmonary pathologies

Respiratory System Physiology: Structure, Function, and Gas Laws

Study Guide - Practice Questions