Q: Minute ventilation ($$V_M) is $$calculated using which formula?

$$V_M = Tidal\ Volume \times Respiratory\ Rate$$

Question 1

Which of the following best describes the function of central chemoreceptors in the regulation of ventilation?

Accepted Answer

They monitor cerebrospinal fluid pH, responding primarily to changes in CO2 levels.

Question 2

During inspiration, which of the following accurately describes the change in thoracic (intrapleural) pressure?

Accepted Answer

It decreases, becoming more negative relative to atmospheric pressure.

Question 3

A patient with chronic obstructive pulmonary disease (COPD) is likely to have which of the following changes in airway resistance, according to the equation $$F = \frac{\Delta P}{R}$$?

Accepted Answer

Increased resistance, resulting in decreased airflow.

Question 4

Which of the following best defines the ventilation-perfusion ratio?

Accepted Answer

The ratio of airflow in the alveoli to blood flow in the pulmonary capillaries.

Question 5

If a person inhales deeply and holds their breath, what happens to the partial pressure of CO2 in their arterial blood?

Accepted Answer

It increases because CO2 is not being exhaled.

Question 6

Which equation correctly represents the chemical reaction catalyzed by carbonic anhydrase during CO2 transport?

Accepted Answer

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

Question 7

Which of the following factors would most likely cause a rightward shift in the hemoglobin-oxygen dissociation curve?

Accepted Answer

Increased CO2, increased temperature, and decreased pH.

Question 8

Minute ventilation ($$V_M) is $$calculated using which formula?

Accepted Answer

$$V_M = Tidal\ Volume 	imes Respiratory\ Rate$$

Question 9

Which of the following best describes the role of pulmonary arteriole smooth muscle in local feedback control?

Accepted Answer

It constricts in response to low alveolar PO2, reducing blood flow to poorly ventilated areas.

Question 10

A patient with restrictive lung disease will most likely have which of the following changes in lung compliance?

Accepted Answer

Decreased compliance, making the lungs harder to inflate.

Question 11

Which of the following is NOT a form in which CO2 is transported in the blood?

Accepted Answer

Bound to albumin.

Question 12

During strenuous exercise, what happens to the hemoglobin-oxygen dissociation curve and why?

Accepted Answer

It shifts right due to increased CO2, temperature, and decreased pH.

Question 13

Which of the following best describes the events of gas exchange during pulmonary exchange?

Accepted Answer

Oxygen diffuses from alveolar air into pulmonary capillaries, while CO2 diffuses from capillaries into alveolar air.

Question 14

Which of the following variables would most directly increase the diffusion rate of a gas across the respiratory membrane?

Accepted Answer

Increased partial pressure gradient of the gas.

Question 15

Which of the following statements about the control centers in the brain stem is correct?

Accepted Answer

The medullary respiratory centers regulate rhythmic breathing.

Question 16

Which of the following best describes the relationship between alveolar ventilation and minute ventilation?

Accepted Answer

Minute ventilation includes dead space, while alveolar ventilation excludes it.

Question 17

A person with asthma experiences bronchoconstriction. Which local feedback mechanism is most likely responsible for this response?

Accepted Answer

Low CO2 levels in the bronchioles cause smooth muscle constriction.

Question 18

Which of the following best describes the structure and function of hemoglobin?

Accepted Answer

Hemoglobin is a tetrameric protein that binds up to four molecules of oxygen.

Question 19

Which of the following best defines 'O2 saturation' as measured by a pulse oximeter?

Accepted Answer

The percentage of hemoglobin binding sites occupied by oxygen.

Respiratory Physiology: Regulation, Mechanics, and Gas Exchange

Study Guide - Practice Questions

Study Guide - Flashcards