22. The Respiratory System

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.

245

The movement of air into and out of the lungs is called __________.

1573

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.

188

What three integrated steps are involved in external respiration?

242

Henry's law states that the total pressure exerted by a mixture of gases is the sum of the pressures exerted independently by each gas in the mixture.

1303

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?

200

Henry's law states that when a gas is in contact with a liquid, that gas will dissolve in the liquid in proportion to its partial pressure.

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

238

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

215

Fill in the blanks: When the alveolar Po₂ decreases, the pulmonary arterioles_____. When the arteriolar Pco₂ increases, the bronchioles_______.

189

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.

237

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.

238

Oxygen and carbon dioxide are exchanged in the lungs and through all cell membranes by a. active transport, b. diffusion, c. filtration, d. osmosis.

274

Doris has an obstruction of her right primary bronchus. As a result, how would the oxygen–hemoglobin saturation curve for her right lung compare with that for her left?

236

Clearly explain the difference between external and internal respiration.

For internal respiration, which of the following must be true:

I. The total amount of CO₂ exchanged equals the amount of O₂ exchanged.

II. Carbon dioxide will move down its concentration gradient to enter the blood.

III. The partial pressure of O₂ in the tissue before gas exchange is ≥ 40 mm Hg.

377

What is it about the structure of the alveoli that makes them an ideal site for gas exchange?

Choose which of the following statements is correct.

377

Why do individuals who are anemic generally not exhibit an increase in respiratory rate or tidal volume, even though their blood is not carrying enough oxygen?

What is one difference between air in the alveoli compared to air in the atmosphere?

Which gradient most directly determines the direction that oxygen and carbon dioxide molecules will move between the air in the alveoli and the blood:

355

What happens to the process of respiration when a person is sneezing or coughing?

225