Question 1

Which statement accurately describes alveolar and systemic gas exchanges

Accepted Answer

The answer of Which statement accurately describes alveolar and systemic...

Question 2

Which statement accurately describes alveolar exchange of oxygen

Accepted Answer

Oxygen diffuses from the alveolus to the blood because the alveolus has a higher partial pressure of oxygen. This is due to the fact that oxygen moves down its concentration gradient, from an area of higher partial pressure to an area of lower partial pressure. In the alveoli, oxygen diffuses from the air with a higher partial pressure into the blood with a lower partial pressure.

Question 3

When blood passes through systemic capillaries,the oxygen saturation of hemoglobin changes

Accepted Answer

In systemic capillaries, oxygen is released from hemoglobin to the surrounding tissues, causing a decrease in oxygen saturation from about 98% to about 75% saturated.

Question 4

The exchange of oxygen and carbon dioxide between the air in the alveoli and blood in the lungs is called

Accepted Answer

External respiration is the exchange of oxygen and carbon dioxide between the air in the alveoli and blood in the lungs. Ventilation refers to the movement of air in and out of the lungs, systemic respiration refers to the exchange of oxygen and carbon dioxide between the blood and body tissues, internal respiration refers to the exchange of gases between the blood and body tissues at the cellular level, and cellular respiration refers to the process by which cells convert glucose into energy.

Question 5

Hemoglobin is crucial for oxygen transport in the blood because oxygen has a _______ solubility coefficient in water.

Accepted Answer

Oxygen has a low solubility coefficient in water, which means that it cannot dissolve easily in the blood plasma. Therefore, the presence of hemoglobin in red blood cells helps to bind and transport oxygen efficiently throughout the body.

Question 6

If someone at sea level is given pure oxygen to breathe,it would cause the oxygen saturation of their hemoglobin

Accepted Answer

The oxygen saturation of hemoglobin at sea level is already close to 100% due to a sufficient partial pressure of oxygen in the air. Therefore, giving pure oxygen to someone at sea level would only increase their hemoglobin oxygen saturation by a small amount since their saturation is already high.

Question 7

An actively contracting muscle will cause local temperature to rise and will produce acidic molecules.Warmth and lower pH cause the oxygen-hemoglobin saturation curve to shift ______ reflecting that hemoglobin releases ______ oxygen.

Accepted Answer

An increase in local temperature and acidity will cause the oxygen-hemoglobin saturation curve to shift to the right, reflecting that hemoglobin releases more oxygen. This is known as the Bohr effect.

Question 8

In a situation where one small bronchus is obstructed,the air in that segment of the lung will develop a high partial pressure of carbon dioxide and a low partial pressure of oxygen.What changes in ventilation and perfusion will occur in that segment in response to this condition

Accepted Answer

The answer of In a situation where one small bronchus...

Question 9

The anatomic features of the respiratory membrane that make alveolar gas exchange so efficient are

Accepted Answer

The respiratory membrane is designed with a large surface area (due to the numerous alveoli in the lungs) and minimal thickness (the diffusion distance for gases is only about 0.5 microns), making it highly efficient for gas exchange across the alveolar-capillary membrane. The other choices are incorrect because high water content, scarcity of capillaries, and hearty thickness do not contribute to the efficiency of gas exchange.

Question 10

About 70% of the CO₂that diffuses into systemic capillaries

Accepted Answer

When CO2 diffuses into systemic capillaries, it combines with water to form carbonic acid (H2CO3), which then dissociates into bicarbonate (HCO3-) and hydrogen ions (H+). This reaction is catalyzed by the enzyme carbonic anhydrase. The bicarbonate ion is the primary form in which CO2 is transported in the blood.

Question 11

From moment to moment,the oxygen partial pressure gradient between systemic capillary blood and systemic cells switches: one moment it favors diffusion toward the blood and the next moment it favors diffusion toward the cells.

Accepted Answer

The answer of From moment to moment,the oxygen partial pressure...

Question 12

Approximately what percent of the oxygen in blood is transported by the hemoglobin of erythrocytes

Accepted Answer

Hemoglobin is the main transporter of oxygen in the blood, and it is estimated that approximately 98% of the oxygen in the blood is bound to hemoglobin. This allows for efficient delivery of oxygen to tissues throughout the body.

Question 13

An increase in the partial pressure of oxygen causes pulmonary arterioles to ________,thereby altering _______ to make gas exchange more efficient.

Accepted Answer

An increase in the partial pressure of oxygen would cause pulmonary arterioles to dilate, thereby increasing perfusion (blood flow) to alveoli with high oxygen levels and improving gas exchange efficiency. Constriction of the pulmonary arterioles would decrease blood flow and potentially lead to decreased gas exchange efficiency. Ventilation is not directly affected by the partial pressure of oxygen.

Question 14

Most carbon dioxide is transported through the blood as bicarbonate dissolved in plasma.

Accepted Answer

This is true. When carbon dioxide enters the bloodstream, it combines with water to form carbonic acid, which then dissociates into bicarbonate and hydrogen ions. The majority of carbon dioxide in the blood is found as bicarbonate ions dissolved in plasma.

Question 15

An increase in the partial pressure of CO₂causes bronchioles to

Accepted Answer

The answer of An increase in the partial pressure of...

Question 16

Imagine that someone is climbing a mountain on a very hot day.As their muscles work,acidic by-products are generated.Describe the relevant responses of the respiratory system and also describe how the affinity for hemoglobin will change under these conditions.

Accepted Answer

The answer of Imagine that someone is climbing a mountain...

Question 17

About 23% of the carbon dioxide in the blood is attached to the _______ portion of hemoglobin.

Accepted Answer

The answer of About 23% of the carbon dioxide in...

Question 18

In addition to oxygen,hemoglobin also transports

Accepted Answer

Hemoglobin also transports carbon dioxide and hydrogen ions.

Question 19

As blood travels through a systemic capillary and exchanges gases with systemic cells,

Accepted Answer

As blood travels through a systemic capillary and exchanges gases with systemic cells, the partial pressure of oxygen in blood decreases as it goes from arterioles to venules. This is because oxygen diffuses out of the blood and into the cells, reducing the concentration of oxygen in the blood. Meanwhile, carbon dioxide diffuses out of the cells and into the blood, increasing the concentration of carbon dioxide in the blood.

Question 20

Which reaction involving CO₂predominates within erythrocytes in the pulmonary capillaries of the lung

Accepted Answer

The answer of Which reaction involving CO₂predominates within erythrocytes in...

Quiz 23: Respiratory System

Which statement accurately describes alveolar and systemic gas exchanges

Which statement accurately describes alveolar exchange of oxygen

When blood passes through systemic capillaries,the oxygen saturation of hemoglobin changes

The exchange of oxygen and carbon dioxide between the air in the alveoli and blood in the lungs is called

Hemoglobin is crucial for oxygen transport in the blood because oxygen has a _______ solubility coefficient in water.

If someone at sea level is given pure oxygen to breathe,it would cause the oxygen saturation of their hemoglobin

An actively contracting muscle will cause local temperature to rise and will produce acidic molecules.Warmth and lower pH cause the oxygen-hemoglobin saturation curve to shift reflecting that hemoglobin releases oxygen.

In a situation where one small bronchus is obstructed,the air in that segment of the lung will develop a high partial pressure of carbon dioxide and a low partial pressure of oxygen.What changes in ventilation and perfusion will occur in that segment in response to this condition

The anatomic features of the respiratory membrane that make alveolar gas exchange so efficient are

About 70% of the CO₂that diffuses into systemic capillaries

From moment to moment,the oxygen partial pressure gradient between systemic capillary blood and systemic cells switches: one moment it favors diffusion toward the blood and the next moment it favors diffusion toward the cells.

Approximately what percent of the oxygen in blood is transported by the hemoglobin of erythrocytes

An increase in the partial pressure of oxygen causes pulmonary arterioles to __,thereby altering _ to make gas exchange more efficient.

Most carbon dioxide is transported through the blood as bicarbonate dissolved in plasma.

An increase in the partial pressure of CO₂causes bronchioles to

Imagine that someone is climbing a mountain on a very hot day.As their muscles work,acidic by-products are generated.Describe the relevant responses of the respiratory system and also describe how the affinity for hemoglobin will change under these conditions.

About 23% of the carbon dioxide in the blood is attached to the _______ portion of hemoglobin.

In addition to oxygen,hemoglobin also transports

As blood travels through a systemic capillary and exchanges gases with systemic cells,

Which reaction involving CO₂predominates within erythrocytes in the pulmonary capillaries of the lung

Quiz 23: Respiratory System

Which statement accurately describes alveolar and systemic gas exchanges

Which statement accurately describes alveolar exchange of oxygen

When blood passes through systemic capillaries,the oxygen saturation of hemoglobin changes

The exchange of oxygen and carbon dioxide between the air in the alveoli and blood in the lungs is called

Hemoglobin is crucial for oxygen transport in the blood because oxygen has a _______ solubility coefficient in water.

If someone at sea level is given pure oxygen to breathe,it would cause the oxygen saturation of their hemoglobin

An actively contracting muscle will cause local temperature to rise and will produce acidic molecules.Warmth and lower pH cause the oxygen-hemoglobin saturation curve to shift ______ reflecting that hemoglobin releases ______ oxygen.

In a situation where one small bronchus is obstructed,the air in that segment of the lung will develop a high partial pressure of carbon dioxide and a low partial pressure of oxygen.What changes in ventilation and perfusion will occur in that segment in response to this condition

The anatomic features of the respiratory membrane that make alveolar gas exchange so efficient are

About 70% of the CO2that diffuses into systemic capillaries

From moment to moment,the oxygen partial pressure gradient between systemic capillary blood and systemic cells switches: one moment it favors diffusion toward the blood and the next moment it favors diffusion toward the cells.

Approximately what percent of the oxygen in blood is transported by the hemoglobin of erythrocytes

An increase in the partial pressure of oxygen causes pulmonary arterioles to ________,thereby altering _______ to make gas exchange more efficient.

Most carbon dioxide is transported through the blood as bicarbonate dissolved in plasma.

An increase in the partial pressure of CO2causes bronchioles to

Imagine that someone is climbing a mountain on a very hot day.As their muscles work,acidic by-products are generated.Describe the relevant responses of the respiratory system and also describe how the affinity for hemoglobin will change under these conditions.

About 23% of the carbon dioxide in the blood is attached to the _______ portion of hemoglobin.

In addition to oxygen,hemoglobin also transports

As blood travels through a systemic capillary and exchanges gases with systemic cells,

Which reaction involving CO2predominates within erythrocytes in the pulmonary capillaries of the lung

An actively contracting muscle will cause local temperature to rise and will produce acidic molecules.Warmth and lower pH cause the oxygen-hemoglobin saturation curve to shift reflecting that hemoglobin releases oxygen.

About 70% of the CO₂that diffuses into systemic capillaries

An increase in the partial pressure of oxygen causes pulmonary arterioles to __,thereby altering _ to make gas exchange more efficient.

An increase in the partial pressure of CO₂causes bronchioles to

Which reaction involving CO₂predominates within erythrocytes in the pulmonary capillaries of the lung