Chapter 22 Flashcards
what organisms use CO2 during the day?
plants
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
E
At standard conditions of temperature and pressure (STP),?
1 mole of gas occupies 22.4 L.
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?
The same—20.95%
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?
The partial pressure of CO2 in Mixture B is 3 times as high as in Mixture A.
What is the relationship between temperature and the solubility of gases in aqueous solutions?
As temperature increases, the solubility of gases in aqueous solutions decreases.
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?
0.2095 atm
In oxygen transport to the mitochondria, diffusion occurs from the
lungs to the red blood cells and red blood cells to the mitochondria.
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.
b
Oxygen transport in animals occurs by
diffusion and convection.
The respiratory gas(es) is (are)
oxygen and carbon dioxide.
In diffusion, materials tend to move in net fashion from regions of
high chemical potential to regions of low chemical potential.
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.
c
During gas diffusion, as the distance between P1 and P2 increases, the rate of movement ___?
decrease
Movement of air into and out of a human lung is an example of ?
tidal flow
As a gas mixture or an aqueous solution flows, gas molecules in the gas or liquid are carried from place to place by
convection
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
A
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.
A
is the law that relates partial pressure and concentration in aqueous solutions.
Henry’s law
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.
b
Gas diffuses from areas of ___ partial pressure to areas of ___ partial pressure, until partial pressure is uniform.
high to low
Diffusion through air is much ___ than diffusion through
___, e.g. 200,000 times faster for O2 and 9000 times
faster for CO2.
faster, water
Diffusion is effective in supplying living cells ___ to
support metabolism over distances of less than 1 mm. At greater distances, convective transport is needed.
O2,
