Chapter 22

Question 1

what organisms use CO2 during the day?

Answer 1

plants

Question 2

Gases diffuse in net fashion from areas of relatively high partial pressure to areas of relatively low partial pressure

a. within gas mixtures.
b. within aqueous solutions.
c. across gas–water interfaces.
d. Both a and b
e. All of the above

Answer 2

E

Question 3

At standard conditions of temperature and pressure (STP),?

Answer 3

1 mole of gas occupies 22.4 L.

Question 4

If the percentage of oxygen in air at sea level is 20.95%, what is the percentage of oxygen in air at the top of Mount Everest?

Answer 4

The same—20.95%

Question 5

Consider two gas mixtures at the same temperature. If the concentration of CO2 in Mixture A is 10 mmol/L and the concentration of CO2 in Mixture B is 30 mmol/L, what is happening?

Answer 5

The partial pressure of CO2 in Mixture B is 3 times as high as in Mixture A.

Question 6

What is the relationship between temperature and the solubility of gases in aqueous solutions?

Answer 6

As temperature increases, the solubility of gases in aqueous solutions decreases.

Question 7

If the partial pressures of nitrogen, argon, and CO2 are 0.7808, 0.0093, and 0.0004 atm respectively, in air at 1 atm, what is the partial pressure of the oxygen in this air?

Answer 7

0.2095 atm

Question 8

In oxygen transport to the mitochondria, diffusion occurs from the

Answer 8

lungs to the red blood cells and red blood cells to the mitochondria.

Question 9

Which of the following statements regarding gas diffusion is true?

a. Gases diffuse only slightly faster through the gas phase than through aqueous solutions.
b. Gases diffuse many times faster through the gas phase than through aqueous solutions.
c. Gases diffuse at equal rates through the gas phase and aqueous solutions.
d. Gases diffuse only slightly slower through the gas phase than through aqueous solutions.
e. Gases diffuse many times slower through the gas phase than through aqueous solutions.

Answer 9

b

Question 10

Oxygen transport in animals occurs by

Answer 10

diffusion and convection.

Question 11

The respiratory gas(es) is (are)

Answer 11

oxygen and carbon dioxide.

Question 12

In diffusion, materials tend to move in net fashion from regions of

Answer 12

high chemical potential to regions of low chemical potential.

Question 13

Which of the following statements regarding air and water is false?

a. Water is denser than air.
b. Water is more viscous than air.
c. Air-breathing animals generally expend more energy ventilating than water-breathing animals.
d. Per unit volume, water holds less oxygen than air.
e. Temperature affects the oxygen solubility in water more than it does in air.

Answer 13

c

Question 14

During gas diffusion, as the distance between P1 and P2 increases, the rate of movement ___?

Answer 14

decrease

Question 15

Movement of air into and out of a human lung is an example of ?

Answer 15

tidal flow

Question 16

As a gas mixture or an aqueous solution flows, gas molecules in the gas or liquid are carried from place to place by

Answer 16

convection

Question 17

Which of the following O2 partial pressure values would you expect to find in the ambient air (AA), arterial blood (AB), and systemic capillary blood (SCB) of an animal?

a. AA = 150 mm Hg; AB = 100 mm Hg; SCB = 70 mm Hg
b. AA = 150 mm Hg; AB = 70 mm Hg; SCB = 100 mm Hg
c. AA = 100 mm Hg; AB = 150 mm Hg; SCB = 70 mm Hg
d. AA = 70 mm Hg; AB = 100 mm Hg; SCB = 70 mm Hg
e. AA = 70 mm Hg; AB = 100 mm Hg; SCB = 150 mm Hg

Answer 17

A

Question 18

Which of the following statements regarding oxygen in a solution becoming bound to hemoglobin is true?

a. Oxygen that is bound to hemoglobin does not contribute to the oxygen partial pressure.
b. Oxygen that is bound to hemoglobin contributes the same amount to partial pressure as when it is dissolved in solution.
c. Oxygen that is bound to hemoglobin contributes more to partial pressure than when it is dissolved in solution.
d. Oxygen that is bound to hemoglobin increases the partial pressure of CO2.
e. Oxygen that is bound to hemoglobin does not change the partial pressure of oxygen.

Answer 18

A

Question 19

is the law that relates partial pressure and concentration in aqueous solutions.

Answer 19

Henry’s law

Question 20

Which of the following statements regarding the water beetle is true?

a. Because the bubble is pure oxygen, it allows the beetle to remain under water for long periods of time.
b. As oxygen in the bubble is used up, oxygen diffuses from the water into the bubble.
c. As CO2 in the bubble increases, it causes oxygen to enter the bubble more readily.
d. As the beetle dives, the increase in pressure drives oxygen into the beetle.
e. The nitrogen in the bubble is responsible for maintaining the oxygen concentration.

Answer 20

b

Question 21

Gas diffuses from areas of ___ partial pressure to areas of ___ partial pressure, until partial pressure is uniform.

Answer 21

high to low

Question 22

Diffusion through air is much ___ than diffusion through
___, e.g. 200,000 times faster for O2 and 9000 times
faster for CO2.

Answer 22

faster, water

Question 23

Diffusion is effective in supplying living cells ___ to

support metabolism over distances of less than 1 mm. At greater distances, convective transport is needed.

Answer 23

O2,