$P_{O_2,\,\text{alveoli}} - P_{O_2,\,\text{capillary}}$

$\text{Efficiency} = \frac{\text{Surface Area} \times \text{Diffusion Coefficient}}{\text{Thickness of Membrane}}$

$\text{Flow} = \frac{\Delta P}{R}$

Question 1

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

Accepted Answer

Movement of air for gas exchange and acid-base balance

Question 2

During inspiration, which muscle is primarily responsible for increasing the volume of the thoracic cavity?

Accepted Answer

Diaphragm

Question 3

Which structure is NOT part of the respiratory exchange zone?

Accepted Answer

Terminal bronchioles

Question 4

What is the main function of goblet cells in the conductive zone of the respiratory system?

Accepted Answer

Production of mucus to trap particles

Question 5

Which equation best represents the partial pressure gradient driving oxygen diffusion from alveoli to blood?

Accepted Answer

$P_{O_2,\,	ext{alveoli}} - P_{O_2,\,	ext{capillary}}$

Question 6

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

Accepted Answer

Type II pneumocytes

Question 7

A patient with damage to the ciliated cells in their trachea would most likely experience which problem?

Accepted Answer

Reduced mucus clearance and increased risk of infection

Question 8

Which of the following best explains why the alveoli are lined with simple squamous epithelium?

Accepted Answer

To maximize surface area and minimize diffusion distance for gas exchange

Question 9

Which of the following is TRUE regarding pulmonary blood circulation?

Accepted Answer

Deoxygenated blood is pumped from the right ventricle to the pulmonary artery

Question 10

Which equation describes the relationship between ventilation and gas exchange efficiency?

Accepted Answer

$	ext{Efficiency} = \frac{	ext{Surface Area} 	imes 	ext{Diffusion Coefficient}}{	ext{Thickness of Membrane}}$

Question 11

Which of the following is a function of the conductive zone but NOT the respiratory exchange zone?

Accepted Answer

Humidification of inspired air

Question 12

A person inhales air containing dust particles. Which mechanism in the conductive zone helps remove these particles?

Accepted Answer

Muco-ciliary escalator

Question 13

Which of the following best describes the role of elastic fibers in the lungs?

Accepted Answer

They provide strength and allow recoil during expiration

Question 14

Which equation represents the bulk flow of air during ventilation?

Accepted Answer

$	ext{Flow} = \frac{\Delta P}{R}$

Question 15

Which of the following would most likely result from a decrease in surfactant production in the alveoli?

Accepted Answer

Increased risk of airway collapse

Question 16

Which structure is responsible for filtering, humidifying, and warming inspired air before it reaches the lungs?

Accepted Answer

Conductive zone (trachea, bronchi, bronchioles)

Question 17

Which of the following is a direct consequence of the large total cross-sectional area of the terminal bronchioles?

Accepted Answer

Decreased velocity of airflow

Question 18

Which cell type in the alveoli is most directly involved in immune defense?

Accepted Answer

Alveolar macrophages

Question 19

Which of the following best describes the pathway of blood flow through the pulmonary circulation?

Accepted Answer

Right ventricle → pulmonary artery → pulmonary capillaries → pulmonary vein → left atrium

Question 20

Which equation best describes the diffusion of gases across the respiratory membrane?

Accepted Answer

$	ext{Rate of diffusion} = \frac{(P_1 - P_2) 	imes A 	imes D}{T}$

The Respiratory System: Structure, Function, and Pulmonary Circulation

Study Guide - Practice Questions