$\text{Minute Ventilation} = \text{Tidal Volume} \times \text{Respiratory Rate}$

Question 1

Which physiological action is primarily responsible for driving ventilation in the human body?

Accepted Answer

Contraction of the diaphragm and intercostal muscles

Question 2

Bulk flow of air in the respiratory system is mathematically modeled by which law, and what is the relevant equation?

Accepted Answer

Ohm's Law for fluids: $Q = \frac{\Delta P}{R}$

Question 3

During forced (voluntary) deep inspiration, which additional muscles are recruited compared to quiet inspiration?

Accepted Answer

Sternocleidomastoid and scalene muscles

Question 4

Which compartment pressures are involved in determining bulk flow of air during ventilation?

Accepted Answer

Alveolar pressure and atmospheric pressure

Question 5

What is the primary defect in the lungs during atelectasis (collapsed lung)?

Accepted Answer

Loss of negative intrapleural pressure

Question 6

Which factor most directly determines the extent of compliance in the lungs?

Accepted Answer

Elasticity of lung tissue and surface tension in alveoli

Question 7

What is the chemical nature of lung surfactant and its primary role?

Accepted Answer

Phospholipid that reduces alveolar surface tension

Question 8

Minute ventilation is calculated using which formula?

Accepted Answer

$	ext{Minute Ventilation} = 	ext{Tidal Volume} 	imes 	ext{Respiratory Rate}$

Question 9

How does respiration differ from ventilation?

Accepted Answer

Respiration refers to gas exchange, while ventilation refers to air movement

Question 10

Which three major factors determine efficient external respiration at the lungs?

Accepted Answer

Surface area, partial pressure gradients, and membrane thickness

Question 11

Where does internal respiration occur?

Accepted Answer

Between systemic capillaries and tissue cells

Question 12

In what two ways is oxygen carried in the bloodstream?

Accepted Answer

Bound to hemoglobin and dissolved in plasma

Question 13

Which factor increases hemoglobin's ability to release oxygen in active tissues?

Accepted Answer

Decreased pH (Bohr effect)

Question 14

Which of the following is NOT a way carbon dioxide is carried in the bloodstream?

Accepted Answer

Bound to albumin

Question 15

What is hypoxia, and how does it differ from hypercapnia?

Accepted Answer

Hypoxia is low oxygen, hypercapnia is high carbon dioxide

Question 16

Which respiratory center in the brain stem is primarily responsible for setting the basic rhythm of breathing?

Accepted Answer

Medullary respiratory center

Question 17

Which structure is NOT directly involved in the control of breathing?

Accepted Answer

Thyroid gland

Question 18

What is the Hering-Breuer reflex and why is it important?

Accepted Answer

It prevents over-inflation of the lungs by inhibiting inspiration

Question 19

Which two major physiological components characterize COPD?

Accepted Answer

Chronic bronchitis and emphysema

Question 20

How does SARS-CoV2 primarily target the respiratory system for infection?

Accepted Answer

By binding to ACE2 receptors on respiratory epithelial cells

BIO EXAM 3C

Study Guide - Practice Questions