22. The Respiratory System

Explain what would happen to the pressure inside a cylinder if you decreased its volume, according to Boyle's law.

Which of the following does not affect the efficiency of pulmonary gas exchange?

a. The surface area of the respiratory membrane

b. The degree of match of ventilation to perfusion

c. The percent saturation of hemoglobin

d. The thickness of the respiratory membrane

Which of the following statements about pulmonary ventilation is false?

a. Normal expiration requires the use of the expiratory muscles to decrease lung volume.

b. The inspiratory muscles increase lung volume, which decreases intrapulmonary pressure.

c. For inspiration to occur, intrapulmonary pressure must decrease below atmospheric pressure.

d. The intrapleural pressure is less than the intrapulmonary pressure; this prevents the lungs from collapsing during expiration.

As a result of a stroke, Mrs. Minnick's swallowing is uncoordinated. What detrimental effect might this have on her ability to breathe?

Which of the following represents intrapleural pressure?

When the inspiratory muscles contract:

a. The size of the thoracic cavity increases in diameter

b. The size of the thoracic cavity increases in length

c. The volume of the thoracic cavity decreases

d. The size of the thoracic cavity increases in both length and diameter

Describe the functional relationships between volume changes and gas flow into and out of the lungs.

Define hyperventilation

If you hyperventilate, do you retain or expel more carbon dioxide?

What effect does hyperventilation have on blood pH?

More than one choice may apply.

Which of the following changes will accompany the loss of lung elasticity associated with aging?

a. Increase in tidal volume

b. Increase in inspiratory reserve volume

c. Increase in residual volume

d. Increase in vital capacity

What happens to the metabolic rate of skeletal muscle tissue during exercise? What waste products are produced from metabolic reactions? How and why does this affect your rate of ventilation during exercise?

The contraction of the diaphragm and the external intercostal muscles begins inspiration. What happens, in terms of volume and pressure changes in the lungs, when these muscles contract?

More than one choice may apply.

During inspiration, intrapulmonary pressure is

a. Greater than atmospheric pressure

b. Less than atmospheric pressure

c. Greater than intrapleural pressure

d. Less than intrapleural pressure

If you swallow a large bite of food without properly chewing it first, you will feel discomfort during ventilation. Explain this, considering the arrangement of the trachea and the esophagus.