Question 1

Which of the following best describes the role of the respiratory system in maintaining blood pH?

Accepted Answer

It regulates blood pH primarily by controlling the rate of pulmonary ventilation, which affects CO$_2$ removal.

Question 2

According to Boyle's Law, what happens to the pressure inside the lungs when the volume of the thoracic cavity increases during inspiration?

Accepted Answer

Pressure inside the lungs decreases, causing air to flow in.

Question 3

Which structure is responsible for preventing food and drink from entering the lower respiratory tract during swallowing?

Accepted Answer

Epiglottis

Question 4

What is the primary function of surfactant produced by Type II alveolar cells?

Accepted Answer

To reduce surface tension in the alveoli, preventing collapse

Question 5

A patient suffers a penetrating chest wound resulting in air entering the pleural cavity. What is the most likely consequence?

Accepted Answer

Collapse of the affected lung due to loss of negative pressure (pneumothorax)

Question 6

Which equation correctly represents the reversible reaction catalyzed by carbonic anhydrase in erythrocytes?

Accepted Answer

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

Question 7

During vigorous exercise, which muscles are recruited to assist with forced inspiration?

Accepted Answer

Serratus anterior, scalenes, pectoralis minor, and sternocleidomastoid

Question 8

Which of the following best explains why oxygen and carbon dioxide move in opposite directions across the respiratory membrane?

Accepted Answer

They diffuse down their respective partial pressure gradients.

Question 9

What effect does increased thickness of the respiratory membrane have on pulmonary gas exchange?

Accepted Answer

It decreases the rate of gas exchange.

Question 10

Which of the following is a consequence of low oxygen (O$_2$) levels in the alveoli on local capillary perfusion?

Accepted Answer

Blood flow to the affected alveoli decreases, providing more time for oxygen loading.

Question 11

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

Accepted Answer

Absorption of nutrients from inhaled air

Question 12

A person with anemia is likely to experience which type of oxygen imbalance?

Accepted Answer

Anemic hypoxia

Question 13

Which of the following best describes the role of hemoglobin in oxygen transport?

Accepted Answer

Hemoglobin reversibly binds up to four oxygen molecules, allowing for loading and unloading depending on tissue needs.

Question 14

Which of the following changes would favor the unloading of oxygen from hemoglobin in active tissues?

Accepted Answer

Increased temperature, increased H$^+$ concentration, and increased PCO$_2$

Question 15

Which of the following is the correct formula for the aerobic respiration reaction in human cells?

Accepted Answer

$C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O$

Question 16

Which of the following respiratory system disorders is most commonly caused by tobacco smoke and is associated with chronic obstruction of airways?

Accepted Answer

Chronic obstructive pulmonary disease (COPD)

Question 17

What is the main reason why CO (carbon monoxide) poisoning is so dangerous?

Accepted Answer

CO binds to hemoglobin at the same site as O$_2$, but does so irreversibly, preventing oxygen transport.

Question 18

Which of the following best describes the function of the pleural cavity?

Accepted Answer

It contains serous fluid that reduces friction and maintains negative pressure to keep the lungs inflated.

Question 19

Which of the following is a direct effect of increased airway resistance on ventilation?

Accepted Answer

Decreased airflow into the alveoli

Anatomy & Physiology: The Respiratory System (BIO 1, Chapter 21)

Study Guide - Practice Questions