Pulmonary Ventilation: Master Breathing Mechanics for MBBS

Question 1

What is the term for the pressure difference between the alveoli and the pleural cavity?

Accepted Answer

Transpulmonary pressure

Answer

Alveolar pressure

Answer

Intrapleural pressure

Answer

Transthoracic pressure

Question 2

Which of the following factors does NOT affect airway resistance?

Accepted Answer

Alveolar surface tension

Answer

Bronchial diameter

Answer

Bronchial length

Answer

Bronchial wall thickness

Question 3

What is the primary role of surfactant in the lungs?

Accepted Answer

To reduce surface tension

Answer

To increase alveolar compliance

Answer

To enhance gas exchange

Answer

To prevent alveolar collapse

Question 4

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

Accepted Answer

Nutrient absorption

Answer

Gas exchange

Answer

Acid-base balance

Answer

Thermoregulation

Question 5

What is the specific function of the diaphragm in pulmonary ventilation?

Accepted Answer

To facilitate inspiration

Answer

To separate the thoracic and abdominal cavities

Answer

To pump blood to the lungs

Answer

To control airway diameter

Question 6

Which of the following is the primary mechanism of pulmonary gas exchange?

Accepted Answer

Diffusion

Answer

Osmosis

Answer

Active transport

Answer

Facilitated diffusion

Question 7

Explain the significance of residual volume (RV) and its impact on respiratory function.

Accepted Answer

Residual volume (RV) is the volume of air remaining in the lungs after a maximum expiration, ensuring ongoing gas exchange and preventing alveolar collapse.

Answer

RV contributes to vital capacity but does not influence the maximum volume of air that can be exhaled.

Answer

RV primarily consists of dead space and does not participate in gas exchange.

Answer

RV is only relevant during forced expirations and has no bearing on normal breathing.

Question 8

What is the term for the body's involuntary breathing response to changes in blood pH?

Accepted Answer

Chemoreflex

Answer

Hering-Breuer reflex

Answer

Baroreflex

Question 9

Which physiological adaptation occurs in the respiratory system during exercise?

Accepted Answer

Increased tidal volume and respiratory rate

Answer

Decreased lung compliance

Answer

Reduced oxygen saturation of hemoglobin

Question 10

Which of the following is NOT a determinant of airway resistance?

Accepted Answer

Surface area of the airway

Answer

Length of the airway

Answer

Diameter of the airway

Answer

Viscosity of the flowing gas

Question 11

What is the functional residual capacity?

Accepted Answer

The volume of gas remaining in the lungs after a normal expiration

Answer

The volume of gas inspired during a normal inspiration

Answer

The maximum volume of gas that can be exhaled after a maximal inspiration

Answer

The volume of gas that is exchanged during each breath

Question 12

Which of the following muscles is primarily responsible for expiration?

Accepted Answer

Abdominal muscles

Answer

Diaphragm

Answer

Intercostal muscles

Answer

Accessory muscles

Question 13

What is the effect of increasing the diameter of an airway on airway resistance?

Accepted Answer

Decreases resistance

Answer

Increases resistance

Answer

No effect on resistance

Answer

Depends on the length of the airway

Question 14

Which of the following is a characteristic of turbulent flow in the airways?

Accepted Answer

High resistance

Answer

Low velocity

Answer

Laminar flow

Answer

No pressure drop

Question 15

What is the primary function of surfactant in the lungs?

Accepted Answer

To reduce surface tension at the air-liquid interface

Answer

To increase airway resistance

Answer

To facilitate gas exchange

Answer

To prevent lung collapse

Question 16

Which of the following is NOT a factor that can affect lung compliance?

Accepted Answer

Airway resistance

Answer

Surface tension

Answer

Lung volume

Answer

Elasticity of the lung tissue

Question 17

What is the primary mechanism for gas exchange in the lungs?

Accepted Answer

Diffusion

Answer

Osmosis

Answer

Active transport

Answer

Facilitated diffusion

Question 18

During a respiratory cycle, which of the following lung volumes undergoes the greatest change?

Accepted Answer

Tidal volume

Answer

Inspiratory capacity

Answer

Residual volume

Answer

Inspiratory reserve volume

Question 19

Which respiratory muscle contraction decreases lung volume during exhalation?

Accepted Answer

Internal intercostal muscle

Answer

Diaphragm

Answer

Accessory muscles of respiration

Answer

External intercostal muscle

Question 20

Which of the following is NOT a factor that influences airway resistance?

Accepted Answer

Blood flow rate

Answer

Airway diameter

Answer

Airway length

Answer

Presence of mucus

Question 21

Gas exchange in the lungs primarily occurs in the:

Accepted Answer

Alveoli

Answer

Trachea

Answer

Bronchioles

Answer

Bronchi

Question 22

The partial pressure of oxygen in the alveoli is approximately:

Accepted Answer

100 mmHg

Answer

50 mmHg

Answer

20 mmHg

Answer

10 mmHg

Question 23

Which of the following accurately describes pulmonary ventilation?

Accepted Answer

The process of moving air into and out of the lungs

Answer

The same as external respiration

Answer

Driven primarily by changes in blood pH

Question 24

The respiratory center in the brainstem primarily responds to changes in:

Accepted Answer

Blood pH

Answer

Blood glucose level

Answer

Blood pressure

Answer

Blood volume

Question 25

The primary role of pulmonary surfactant is to:

Accepted Answer

Reduce surface tension in the alveoli

Answer

Increase airway diameter

Answer

Enhance gas exchange