Gas Exchange: Principles and Mechanisms - Physiology Quizzes

Question 1

The partial pressure of oxygen in the alveoli is approximately:

Accepted Answer

100 mmHg

Answer

40 mmHg

Answer

150 mmHg

Answer

200 mmHg

Question 2

Diffusion of gases across the respiratory membrane occurs:

Accepted Answer

From high partial pressure to low partial pressure

Answer

From low partial pressure to high partial pressure

Answer

In both directions simultaneously

Answer

Only during expiration

Question 3

The primary function of hemoglobin in the respiratory system is:

Accepted Answer

Transport of oxygen

Answer

Transport of carbon dioxide

Answer

Regulation of pH

Answer

Immune defense

Question 4

The shape of the oxygen-hemoglobin dissociation curve reflects:

Accepted Answer

The affinity of hemoglobin for oxygen

Answer

The rate of oxygen diffusion

Answer

The partial pressure of carbon dioxide

Answer

The temperature of the blood

Question 5

The Bohr effect refers to the:

Accepted Answer

Effect of partial pressure of carbon dioxide on hemoglobin-oxygen binding

Answer

Effect of pH on hemoglobin-oxygen binding

Answer

Effect of temperature on hemoglobin-oxygen binding

Answer

Effect of partial pressure of oxygen on hemoglobin-carbon dioxide binding

Question 6

Which of the following is NOT a characteristic of type II respiratory failure?

Accepted Answer

Normal blood gas values

Answer

Hypoxemia with hypercapnia

Answer

Hypoxemia without hypercapnia

Answer

Hypercapnia without hypoxemia

Question 7

The respiratory quotient (RQ) is a measure of:

Accepted Answer

The ratio of carbon dioxide production to oxygen consumption

Answer

The ratio of oxygen consumption to carbon dioxide production

Answer

The ratio of alveolar ventilation to carbon dioxide production

Answer

The ratio of dead space to tidal volume

Question 8

Which of the following methods is used to measure lung function?

Accepted Answer

Spirometry

Answer

Oximetry

Answer

Electrocardiography

Answer

Magnetic resonance imaging

Question 9

How does Fick's Law help us understand gas exchange across the respiratory membrane?

Accepted Answer

Fick's Law links gas flow, pressure difference, and membrane permeability.

Answer

Fick's Law is used only to calculate oxygen uptake in the lungs.

Answer

Fick's Law applies only to gas exchange in the lungs, not in tissues.

Question 10

Which primary factor drives the diffusion of gases across the respiratory membrane?

Accepted Answer

Partial pressure gradient

Answer

Temperature

Answer

Membrane thickness

Answer

pH

Question 11

Which of the following is NOT a function of hemoglobin?

Accepted Answer

Regulation of blood pressure

Answer

Oxygen transport

Answer

Carbon dioxide transport

Answer

Buffering of blood pH

Question 12

Which of the following is characteristic of respiratory distress syndrome?

Accepted Answer

Alveolar collapse

Answer

Increased production of surfactant

Answer

Increased lung compliance

Answer

Normal oxygen saturation

Question 13

The primary stimulus for respiratory rate regulation is:

Accepted Answer

Arterial carbon dioxide tension

Answer

Arterial oxygen tension

Answer

pH

Answer

Temperature

Question 14

Which of the following is a characteristic of emphysema?

Accepted Answer

Reduced surface area for gas exchange

Answer

Increased lung compliance

Answer

Increased diffusion capacity

Answer

Normal airway resistance

Question 15

Which of the following is a clinical manifestation of hypoxemia?

Accepted Answer

Cyanosis

Answer

Polycythemia

Answer

Bradycardia

Answer

Hyperventilation

Question 16

The exchange of gases between the lungs and the blood is known as:

Accepted Answer

External respiration

Answer

Internal respiration

Answer

Cellular respiration

Answer

Gas diffusion

Question 17

Which factor primarily determines the rate of diffusion of gases across the respiratory membrane?

Accepted Answer

Partial pressure gradient of the gas across the membrane

Answer

Surface area of the respiratory membrane

Answer

Thickness of the respiratory membrane

Answer

Solubility of the gas in blood

Question 18

What is the primary role of hemoglobin in respiratory physiology?

Accepted Answer

To transport oxygen

Answer

To transport carbon dioxide

Answer

To regulate pH

Answer

To facilitate diffusion of gases across the respiratory membrane

Question 19

What mechanism is responsible for the movement of gases from the alveoli to the pulmonary capillaries?

Accepted Answer

Diffusion

Answer

Active transport

Answer

Osmosis

Answer

Bulk flow

Question 20

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

Accepted Answer

Nutrient absorption

Answer

Gas exchange

Answer

Regulation of body temperature

Answer

Thermoregulation

Question 21

What is the role of surfactant in the respiratory system?

Accepted Answer

To reduce surface tension in the alveoli

Answer

To facilitate diffusion of gases across the respiratory membrane

Answer

To protect the respiratory tract from infection

Answer

To regulate airway resistance

Question 22

What is the partial pressure of oxygen in the alveoli in an individual breathing normal air at sea level?

Accepted Answer

100 mmHg

Answer

90 mmHg

Answer

80 mmHg

Answer

70 mmHg

Question 23

Which of the following mechanisms is primarily responsible for the movement of respiratory gases across the respiratory membrane?

Accepted Answer

Diffusion

Answer

Facilitated diffusion

Answer

Active transport

Answer

Osmosis

Question 24

The protein responsible for transporting oxygen in the blood is:

Accepted Answer

Hemoglobin

Answer

Ferritin

Answer

Myoglobin

Answer

Cytochrome

Question 25

The oxygen-hemoglobin dissociation curve is best described as:

Accepted Answer

Sigmoidal

Answer

Hyperbolic

Answer

Exponential

Answer

Linear

Question 26

The primary function of surfactant in the lungs is to:

Accepted Answer

Reduce surface tension in the alveoli

Answer

Increase lung compliance

Answer

Prevent alveolar collapse

Answer

Enhance gas exchange

Question 27

Which of the following respiratory disorders is characterized by impaired diffusion of gases across the respiratory membrane?

Accepted Answer

Emphysema

Answer

Bronchitis

Answer

Asthma

Question 28

The respiratory quotient (RQ) is a measure of:

Accepted Answer

The ratio of carbon dioxide produced to oxygen consumed

Answer

The ratio of oxygen consumed to carbon dioxide produced

Answer

The difference between oxygen consumed and carbon dioxide produced