22. The Respiratory System

You and a friend are having a contest to see who can hold his or her breath the longest. Your friend hyperventilates before holding his breath, and subsequently wins the contest. Why did hyperventilation give him an advantage?

Which of the following determines the direction of gas movement?

a. Solubility in water

b. Partial pressure gradient

c. Temperature

d. Molecular weight and size of the gas molecule

When determining the directions that molecules will move in external and internal respiration:

Henry's law states that the degree to which a gas dissolves in a liquid is determined by its:

a. Partial pressure

b. Solubility

c. Surface tension

d. Both a and b are correct

e. All of the above are correct

What three integrated steps are involved in external respiration?

What is the significance of

(c) Henry's law to the process of respiration?

What is the significance of

(b) Dalton's law, to the process of respiration?

When the alveolar Pco₂ decreases, the pulmonary arterioles_____. When the arteriolar Pco₂ increases, the bronchioles_______.

Which of the following does not occur in internal respiration?

(a) Oxygen diffuses from the blood to the interstitial spaces.

(b) Carbon dioxide diffuses from the interstitial spaces to the blood.

(c) Hemoglobin binds more oxygen.

(d) Bicarbonate ions are formed in red blood cells.

(e) Chloride ions diffuse into red blood cells as bicarbonate ions diffuse out.

Gas exchange at the blood air barrier is efficient because

(a) The differences in partial pressure are substantial

(b) The gases are lipid soluble

(c) The total surface area is large

(d) Of all of these

Oxygen and carbon dioxide are exchanged in the lungs and through all cell membranes by:

a. Active transport

b. Diffusion

c. Filtration

d. Osmosis