Question 1

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

Accepted Answer

It reduces surface tension, preventing alveolar collapse and making gas exchange more efficient.

Question 2

A patient with emphysema has difficulty exhaling air from the lungs. Which structural change in the lungs is primarily responsible for this symptom?

Accepted Answer

Destruction of alveolar walls leading to loss of lung elasticity

Question 3

Which of the following is NOT a function of the nose in the respiratory system?

Accepted Answer

Initiating the cough reflex

Question 4

During inspiration, which of the following occurs to allow air to flow into the lungs?

Accepted Answer

The diaphragm contracts, increasing thoracic volume and decreasing intrapulmonary pressure.

Question 5

Which region of the pharynx is exclusively a passageway for air and is closed off by the uvula during swallowing?

Accepted Answer

Nasopharynx

Question 6

Which of the following best explains why the left lung has fewer lobes than the right lung?

Accepted Answer

The left lung is smaller to accommodate the heart.

Question 7

A person inhales deeply and then forcibly exhales as much air as possible. Which respiratory volume is being measured?

Accepted Answer

Vital capacity

Question 8

Which of the following equations correctly represents the calculation of vital capacity ($$VC) in $$the lungs?

Accepted Answer

$$VC = Tidal\ Volume + Inspiratory\ Reserve\ Volume + Expiratory\ Reserve\ Volume$$

Question 9

Which of the following is a primary function of the larynx?

Accepted Answer

Routing air and food into proper channels and housing the vocal cords

Question 10

What is the main reason that rising levels of $$CO_2 in $$the blood stimulate an increase in respiratory rate?

Accepted Answer

High $$CO_2$$ levels decrease blood pH, which stimulates chemoreceptors.

Question 11

Which of the following best describes the role of the pleural fluid?

Accepted Answer

It acts as a lubricant, reducing friction and helping the lungs adhere to the thoracic wall.

Question 12

A patient with chronic bronchitis is likely to experience which of the following symptoms due to changes in the respiratory passages?

Accepted Answer

Excessive mucus production and inflammation of the mucosa

Question 13

Which of the following statements about the respiratory membrane is correct?

Accepted Answer

It is a thin barrier formed by alveolar and capillary walls, allowing efficient gas exchange by diffusion.

Question 14

Which of the following best explains why poor ventilation in a region of the lung leads to constriction of pulmonary capillaries in that area?

Accepted Answer

To match perfusion with ventilation and maximize gas exchange efficiency

Question 15

Which of the following is the correct sequence of structures that air passes through from the trachea to the alveoli?

Accepted Answer

Trachea → Bronchi → Bronchioles → Alveolar ducts → Alveoli

Question 16

Which of the following is a distinguishing feature of asthma compared to COPD?

Accepted Answer

Asthma involves reversible airway obstruction and is often triggered by inflammation.

Question 17

Which of the following best describes the effect of smoking on the tracheal cilia?

Accepted Answer

Smoking destroys cilia, leading to mucus accumulation and increased coughing.

Question 18

Which of the following is the main function of the conducting zone of the respiratory system?

Accepted Answer

Purifying, humidifying, and warming incoming air

Question 19

Which of the following is the most powerful respiratory stimulant?

Accepted Answer

Rising levels of carbon dioxide ($$CO_2)$$

Question 20

A patient at high altitude is likely to experience an increase in respiratory rate. Which chemical factor is primarily responsible for this response?

Accepted Answer

Decreased $$O_2$$ levels in the blood

Chapter 22: The Respiratory System – Structure, Function, and Regulation

Study Guide - Practice Questions