Lab Homework 3 CH 23 HW
Which breathing center promotes inhalation by stimulating the DRG?
Apneustic center
If a person contracts pneumonia, inflammation occurs in the lobules of the lung, causing fluid leakage into the alveoli. Which of the following best describes the affect this has on gas exchange?
As the alveoli fill with fluid, air cannot reach the alveolar surface and gas exchange cannot occur, compromising the function of the respiratory membrane.
What is the difference between TLC and VC?
TLC includes RV; VC does not include RV
During forced exhalation, _______.
the internal intercostals contract
Under normal conditions, the forced expiratory volume is normally _______.
75 - 85% of the vital capacity
Which of the following variables is NOT monitored by the medullary breathing centers?
Air humidity
When levels of CO2 rise in the blood, which of the following changes will occur? a. pH levels decrease. b. Hemoglobin releases O2. c. Levels of HCO3- increase. d. All of the above changes will occur with an increase in CO2
All of the above changes will occur with an increase in CO2
Carbon monoxide poisoning is possible because carbon monoxide binds readily with heme at very low partial pressures compared to those of oxygen. Besides partial pressure, what else determines the affinity of oxygen molecules for heme? a. BPG concentration b. temperature c. pH levels d. All of the listed responses are correct.
All of the listed responses are correct
No air is moving in or out of the lungs in this image. Which of the following describes the pressures of the atmosphere ("P outside") and the lungs ("P inside")?
P inside = P outside
What is the function of the cell indicated by the red arrow?
prevent alveolar collapse
Cystic fibrosis is an inherited respiratory disorder in which the mucus escalator no longer functions because of the presence of excessively dense and viscous mucus. Which of the following components of the respiratory system are affected by cystic fibrosis? a. cilia b. lungs c. goblet cells
All of the listed responses are correct
Which of the following would be the oxygen pressure entering, and leaving, this capillary?
entering Po2 95 mm Hg, leaving Po2 40 mm Hg
__________ percentage of carbon dioxide is bound to hemoglobin forming __________.
23%, carbaminohemoglobin
If the production of surfactant by type II alveolar cells (septal cells) is inadequate, which of these changes is expected? a. alveolar collapse b. increased inspiratory effort c. increased surface tension in the liquid coating the alveolar surface d. All of these changes can be expected if the production of surfactant is inadequate
All of these changes can be expected if the production of surfactant is inadequate
Which class of sensory receptor can modify respiratory reflexes? a. chemoreceptors b. stretch receptors c. nociceptors d. All of these sensory receptors can modify respiratory reflexes
All of these sensory receptors can modify respiratory reflexes
Which of the following statements correctly contrasts the dorsal respiratory group (DRG) and the ventral respiratory group (VRG)?
The DRG is mainly active during inspiration, while the VRG is primarily active during expiration.
In a condition known as pneumothorax, the integrity of the pleural cavity is lost, which leads to a collapsed lung. What is one explanation for why this occurs?
The pleural fluid that bonds the visceral and parietal pleurae together is broken by air.
Lung cancer claims more lives than other cancers, according to the Centers for Disease Control. Because of their high mitotic rate, epithelial cells are particularly prone to tumor formation. Choose the best answer as to where within the respiratory tract you would NOT find such epithelial cells? a. lining the trachea b. lining the pharynx c. within the walls of the alveoli d. You would find epithelial cells in all of the listed answer choices.
You would find epithelial cells in all of the listed answer choices
The minute ventilation is _______.
calculated by multiplying the rate of respiration times TV
Which of the following is a passive process?
expiration
When the radius of the airway was decreased, _______.
expiratory reserve volume decreased
Dalton's law states that:
in a mixture of gases such as air, the total pressure is the sum of the individual partial pressures of the gases in the mixture
Where is more than 70 percent of the carbon dioxide carried in the blood?
in the plasma, as dissolved CO2 or HCO3 -
In patients with emphysema, the alveolar surface area decreases, thereby decreasing the area available for gas exchange. In addition, vascularity declines, making it harder still to transport adequate amounts of oxygen. Which of the following would help an emphysema patient bind as much oxygen as possible with the limited heme units available?
inhaling oxygen at higher partial pressures
Boyle's law states that gas pressure is __________.
inversely proportional to volume
When the diaphragm contracts, _______.
it flattens out
Very aggressive pathogens such as the bacterium responsible for tuberculosis can easily overwhelm the protective features of the respiratory system. Less aggressive pathogens may be stopped by all of the following EXCEPT __________.
olfactory epithelium
What is the driving force for the movement of air into the lungs?
the pressure gradient
Henry's law states that:
the volume of gas that will dissolve in a solvent is proportional to the solubility of the gas and the gas pressure
The volume of air moved in a single respiratory cycle is called ____.
tidal volume
Which of the following describes the volume of air exhaled during passive breathing?
tidal volume
