Question 1

Which of the following best explains why hemoglobin's oxygen saturation curve is S-shaped (sigmoidal) rather than linear?

Accepted Answer

The binding of each O2 molecule increases hemoglobin's affinity for additional O2 molecules.

Question 2

A patient with a fever (body temperature of 40°C) is likely to experience which change in the oxygen-hemoglobin dissociation curve?

Accepted Answer

The curve will shift to the right, decreasing hemoglobin's affinity for O2.

Question 3

Which equation represents the formation of bicarbonate ions from carbon dioxide in red blood cells?

Accepted Answer

$$\mathrm{CO_2$ + H_2O \rightarrow H_2CO_3 \rightarrow H^+ + $$HCO_3$$^-}$$

Question 4

During vigorous exercise, which of the following is most likely to occur regarding blood gases and pH?

Accepted Answer

PCO2, PO2, and pH remain surprisingly constant due to increased ventilation.

Question 5

Which of the following best describes the Bohr effect?

Accepted Answer

Decreased pH and increased PCO2 weaken the Hb-O2 bond, enhancing O2 unloading.

Question 6

Which of the following is a consequence of the chloride shift in systemic capillaries?

Accepted Answer

Cl– moves into RBCs as HCO3– leaves.

Question 7

A person with chronic bronchitis is most likely to experience which of the following symptoms?

Accepted Answer

Frequent pulmonary infections and excessive mucus production.

Question 8

Which equation best represents the carbonic acid–bicarbonate buffer system's response to increased H+ concentration in blood?

Accepted Answer

$$\mathrm{H^+ + $$HCO_3$$^- \rightarrow H_2CO_3 \rightarrow CO_2$ + H_2O}$$

Question 9

Which of the following is true regarding the Haldane effect?

Accepted Answer

The lower the PO2 and hemoglobin O2 saturation, the more CO2 can be carried in blood.

Question 10

Which neural structure is primarily responsible for generating the basic rhythm of breathing?

Accepted Answer

Ventral respiratory group (VRG) in the medulla

Question 11

A swimmer hyperventilates before diving. What is the physiological risk associated with this behavior?

Accepted Answer

Delayed urge to breathe, risking dangerously low PO2 levels.

Question 12

Which of the following is most likely to stimulate peripheral chemoreceptors to increase ventilation?

Accepted Answer

A drop in arterial PO2 below 60 mm Hg.

Question 13

Which of the following best describes the effect of rapid, deep breathing on blood pH?

Accepted Answer

It decreases CO2 in blood, causing a rise in pH.

Question 14

Which of the following is a feature of emphysema?

Accepted Answer

Permanent enlargement of alveoli and destruction of alveolar walls.

Question 15

Which of the following is true regarding oxygen transport in blood?

Accepted Answer

98.5% of oxygen is bound to hemoglobin in red blood cells.

Question 16

Which of the following is a likely consequence of hypoxemic hypoxia?

Accepted Answer

Abnormal ventilation or pulmonary disease leading to low levels of oxygen in air.

Question 17

Which of the following best describes the effect of increased BPG concentration on hemoglobin?

Accepted Answer

It decreases hemoglobin's affinity for O2, enhancing O2 unloading.

Question 18

Which of the following is true regarding the response to high altitude?

Accepted Answer

Minute ventilation increases and stabilizes at a higher level than at sea level.

Question 19

Which of the following is a function of the pontine respiratory centers?

Accepted Answer

Smooth out transitions between inspiration and expiration.

Transport and Regulation of Respiratory Gases: Oxygen and Carbon Dioxide in the Human Body

Study Guide - Practice Questions