Deck 37: Gas Exchange Transport

Question 1

Each hemoglobin molecule can carry how many oxygen molecules?

A)One
B)Two
C)Four
D)Eight

Answer 1

C

Question 2

Carbon dioxide is carried in three forms in the blood. Ranking them from greatest to least amount carried, the sequence would be:

A)dissolved in the plasma, carbaminohemoglobin, and bicarbonate ion.
B)carbaminohemoglobin, bicarbonate ion, and dissolved in plasma.
C)bicarbonate ion, dissolved in plasma, and carbaminohemoglobin.
D)bicarbonate ion, carbaminohemoglobin, and dissolved in plasma.

Answer 2

D

Question 3

The PCO₂ in the atmosphere is:

A)less than in the alveolar air.
B)greater than in the alveolar air.
C)equal to the alveolar air.
D)greater than arterial blood.

Answer 3

A

Question 4

The partial pressure of oxygen in an artery is always lower than the partial pressure of oxygen in a vein.

Question 5

Dalton law states that the partial pressure of a gas in a mixture of gases is _____ to the total pressure of the mixture.

A)inversely related to the concentration of that gas in the mixture and
B)directly related to the concentration of that gas in the mixture and
C)directly related to the concentration of that gas in the mixture and inversely related
D)inversely related to the concentration of that gas in the mixture and directly related

Question 6

Each hemoglobin molecule can carry how many carbon dioxide molecules?

A)Two
B)Four
C)Eight
D)Hemoglobin cannot carry carbon dioxide molecules.

Question 7

By the time the blood leaves the lung capillaries to return to the heart, what percentage of the blood's hemoglobin has united with oxygen?

A)55%
B)63%
C)82%
D)97%

Question 8

Which of the following is not a means of transporting oxygen in the blood?

A)As oxyhemoglobin
B)Combined with the bicarbonate ion (HCO3-)
C)Dissolved in the plasma
D)All of the above are used to transport oxygen in the blood.

Question 9

One hundred milliliters of arterial blood contains approximately what volume percent of oxygen?

A)10%
B)15%
C)20%
D)25%

Question 10

A drop in the body's production of carbonic anhydrase would hinder the formation of:

A)carbonic acid.
B)oxyhemoglobin.
C)carbaminohemoglobin.
D)All of the above are correct.

Question 11

The symbol HbNCOOH- is used for:

A)carbonic anhydrase.
B)carbaminohemoglobin.
C)the heme group.
D)the bicarbonate ion.

Question 12

The PCO₂ in alveolar air is _____ blood.

A)less than in the systemic venous
B)greater than in the systemic venous
C)equal to the systemic arterial
D)Both A and C are correct.

Question 13

The major form by which carbon dioxide is transported in the circulatory system is:

A)in solution.
B)as bicarbonate ions.
C)as carbaminohemoglobin.
D)none of the above.

Question 14

About 98.5% of the oxygen carried by systemic arterial blood is attached to:

A)bicarbonate ions.
B)hemoglobin.
C)carbaminohemoglobin.
D)chloride ions.

Question 15

Which of the following helps determine the amount of oxygen that diffuses into the blood each minute?

A)The total functional surface area of the respiratory membrane
B)Alveolar ventilation
C)The oxygen pressure gradient between alveolar air and incoming pulmonary blood
D)All of the above help determine the amount of oxygen that diffuses into the blood each minute.

Question 16

If anything decreases alveolar PO₂, how does that affect the alveolar-blood oxygen pressure gradient?

A)Anything that decreases alveolar PO2 tends to increase the alveolar-blood oxygen pressure gradient and, therefore, tends to increase the amount of oxygen entering the blood.
B)Anything that decreases alveolar PO2 tends to decrease the alveolar-blood oxygen pressure gradient and, therefore, tends to decrease the amount of oxygen entering the blood.
C)Anything that decreases alveolar PO2 tends to increase the alveolar-blood diffusion rate and, therefore, tends to increase the amount of oxygen entering the blood.
D)Anything that decreases PO2 tends to increase arterial-blood PO2 and, therefore, tends to decrease the amount of oxygen entering the blood.

Question 17

If a person were skiing high up in the mountains, she might feel that she is having trouble breathing (getting enough oxygen in her blood). This is because the:

A)thoracic cavity has a difficult time lowering the internal pressure below the lower atmospheric pressure.
B)lower atmospheric pressure lowers the PO2 and the diffusion gradient between the blood and the atmosphere is less.
C)lower atmospheric pressure lowers the PO2 and the diffusion gradient between the blood and the atmosphere is greater.
D)physiological dead air space increases and atmospheric pressure decreases.

Question 18

The partial pressure exerted by oxygen in a liquid is called oxygen tension.

Question 19

Which of the following would have the greatest accelerating effect on the dissociation of oxygen from hemoglobin?

A)Increased PO2
B)Decreased PCO2
C)Decreased PO2 and decreased PCO2
D)Decreased PO2 and increased PCO2

Question 20

The approximate partial pressure of oxygen at standard atmospheric pressure is about _____ mm Hg.

A)23
B)160
C)300
D)590

Question 21

Under usual conditions, the oxygen saturation of systemic venous blood is 75%.

Question 22

The terms oxygen partial pressure and oxygen tension are interchangeable.

Question 23

Under usual conditions, the partial pressure of oxygen in systemic venous blood is approximately 87 mm Hg.

Question 24

The PO₂ is higher in the femoral artery than in the femoral vein.

Question 25

For cells to get oxygen, they must have an oxygen partial pressure lower than the arterial blood serving them.

Question 26

Iron is important in hemoglobin because it carries oxygen to the cells and carbon dioxide away from the cells.

Question 27

About 20% of the carbon dioxide that is carried in the blood is carried on hemoglobin attached to the acid group of an amino acid.

Question 28

Blood is distributed through the capillaries in a layer so thin that each red blood cell comes in contact with the alveolar-capillary membrane.

Question 29

Because of tissue layers between alveolar air and the blood supply, arterial blood PO₂ is always less than alveolar PO₂.

Question 30

In the lung oxygen moves down its pressure gradient, whereas carbon dioxide moves up its pressure gradient.

Question 31

When cells increase the rate of oxygen usage, there is an increase in the delivery of oxygen to the cells.

Question 32

In the lung as the partial pressure of oxygen of the blood goes up, the partial pressure of oxygen in the alveolar air goes down proportionally.

Question 33

The partial pressure of oxygen in the alveolar air is equal to the partial pressure of oxygen in the systemic venous blood.

Question 34

One reason that carbon monoxide gas is so dangerous is that it attaches to hemoglobin more readily than does oxygen gas.

Question 35

Oxygenated blood contains equal amounts of both dissolved oxygen and oxygen combined with hemoglobin.

Question 36

On a percentage basis, there is more carbon dioxide dissolved in the plasma than there is oxygen dissolved in the plasma.

Question 37

If the PCO₂ is greater in the cells than in the intercellular fluid, CO₂ will remain in the cells.

Question 38

One factor that determines the amount of oxygen transferred from the lungs to the blood is the total functional surface area of the respiratory membrane.

Question 39

The Bohr effect describes the effect of an increased PCO₂ causing a decreased affinity between hemoglobin and oxygen.

Question 40

An increase in the plasma PCO₂ and a decrease in PO₂ cause an increase in the dissociation of CO₂ from hemoglobin.

Question 41

To produce the highest possible oxygen concentration in the blood, gas exchange occurs in only one direction at the respiratory membrane-from the lung to the blood.

Question 42

There is one iron atom in one heme group.

Question 43

Although interstitial fluid and intracellular fluid oxygen partial pressure values are not definitely established, they are known to stay within a very narrow range.

Question 44

About 10% of the carbon dioxide carried in the blood is simply dissolved in the plasma.

Question 45

White blood cells do not have a role in oxygen transport.

Question 46

Hemoglobin is made up of four polypeptide chains: an alpha, a beta, a gamma, and a delta.

Question 47

The enzyme in blood plasma that helps form carbaminohemoglobin is carbonic anhydrase.

Question 48

An increase in carbon dioxide would have the opposite effect on oxygen-hemoglobin dissociation than would a drop in blood pH.

Question 49

Hemoglobin can carry oxygen more efficiently than it can carry carbon dioxide because all four polypeptide chains can carry oxygen, but only the beta chain can carry carbon dioxide.

Question 50

There are six iron atoms in a single hemoglobin molecule.

Question 51

According to the rate laws of chemistry, the more carbon dioxide in the blood, the more carbaminohemoglobin will be formed.

Question 52

The Bohr effect explains what happens to oxygen, whereas the Haldane effect explains what happens to carbon dioxide.

Question 53

The presence of hemoglobin in the blood approximately doubles the oxygen-carrying capacity of plasma alone.

Question 54

In a resting person, the oxygen saturation in the systemic venous blood is still about 50%.

Question 55

The formation of carbaminohemoglobin is a reversible reaction.

Question 56

An increase in the partial pressure of carbon dioxide decreases the affinity between hemoglobin and oxygen. This is called a right shift, or the Haldane effect.

Question 57

Carbonic acid forms when carbon dioxide reacts with water in the blood plasma.

Question 58

Hemoglobin is a quaternary protein consisting of four tertiary polypeptide chains.

Question 59

The chloride shift is an important step of oxygen transport in the blood.

Question 60

The transport of carbon dioxide will tend to lower blood pH.

Question 61

Explain Dalton law as it relates to the movement of oxygen from the lungs into the circulatory system.

Question 62

Explain the process by which oxygen is transported by the blood.

Question 63

Briefly describe and diagram the oxygen-hemoglobin dissociation curve.

Question 64

Explain why less oxygen would enter the blood at a high altitude than would enter the blood at sea level.

Question 65

Explain the process by which carbon dioxide is transported by the blood.

Question 66

Assume the percent of oxygen in the air is constant (about 21%). What is the partial pressure of oxygen in the mountains, where the atmospheric pressure is 725 mm Hg?

Question 67

Identify the major factors that help determine the amount of oxygen that diffuses into the blood each minute.

Question 68

The structural designs of alveoli and capillaries in lung tissue are such that they facilitate oxygen diffusion. List examples that support the concept that structure determines function.

Question 69

In order for the cells to get the correct amount of oxygen, the oxygen level in the interstitial fluid must be less than that of the cells.

Question 70

Increased cellular activity would decrease the carbon dioxide gradient between the cells and the arterial blood.

Question 71

Increased cellular activity would increase the oxygen gradient between the cells and the arterial blood.