ch 17

What is a function of the pleural fluid?

• To keep the thoracic cavity from collapsing

• To help oxygen diffuse into the blood

• To hold the lungs to the thoracic wall

• To humidify inhaled air

Like the cardiovascular system, what is the primary determinant of resistance to flow in the respiratory system?

• tube length

• air viscosity

• air density

• tube radius

Which is the best definition of anatomical dead space?

• the ventilation rate

• the volume of the conducting system

• The volume of the exchange portion of the respiratory system

• the tidal volume

Which is NOT considered to be a primary function of the respiratory system?

• vocalization

• regulation of pH

• regulation of water balance

• gas exchange

The upper respiratory tract includes all EXCEPT which of the following?

• nasal cavity

• larynx

• mouth

• lungs

Type II alveolar cells

• allow rapid diffusion of gases through their thin membranes, secrete a chemical known as surfactant, and are phagocytic

• secrete a chemical known as surfactant

• are phagocytic

• none are true

Surfactant

• phagocytizes small particulate matter.r

• replaces mucus in the alveoli.

• protects the surface of the lungs.

• helps prevent the alveoli from collapsing

Dalton's law states that

• gas volume and temperature are directly proportional.

• in a mixture of gases like air, the total pressure is the sum of the individual partial pressures of the gases in the mixture.

• gas volume and temperature gas volume and pressure are inversely proportional.

• the volume of gas that will dissolve in a solvent is proportional to the solubility of the gas and the gas pressure.

air moves into the lungs because

• the gas pressure in the lungs is less than outside pressure.

• the thorax is muscular

• contraction of the diaphragm decreases the volume of the pleural cavity.

• none

Chronic inhalation of fine particles that reach the alveoli leads to ________ lung disease.