01
True or false
1 point
During quiet exhalation, the diaphragm and external intercostal muscles relax, and air flows out as pressure inside the lungs rises.
Free Practice Quiz Question List
5 The Respiratory System Online Quiz Questions
Use this free practice quiz with 20 questions to review 5 The Respiratory System, test your knowledge, and prepare for your next test or exam.
20 questions
02
Choose one
1 point
Which measure most directly describes the fresh air reaching the gas-exchanging surfaces of the lungs each minute?
- A
The total amount of air moved into and out of the lungs each minute
- B
The amount of fresh air reaching the alveoli each minute
- C
The amount of air remaining in the conducting airways
- D
The volume of blood flowing through pulmonary capillaries each minute
03
Fill in the blank
1 point
Oxygen and carbon dioxide cross the thin alveolar walls by .
04
Written response
1 point
What is the name of the gas-exchange process between the alveoli and pulmonary blood?
05
Choose one
1 point
What term describes blood flow through the pulmonary capillaries that supports gas exchange in the lungs?
- A
Ventilation
- B
Diffusion
- C
Perfusion
- D
Internal respiration
06
True or false
1 point
Most oxygen in the blood is carried attached to hemoglobin rather than dissolved directly in plasma.
- A
True
- B
False
07
Fill in the blank
1 point
Most carbon dioxide is transported in plasma as .
08
Choose one
1 point
During exercise, which statement best describes the role of accessory muscles in forced breathing?
- A
Accessory muscles are used only for gas exchange in the alveoli.
- B
Accessory muscles can help move air more rapidly during forced breathing.
- C
Accessory muscles convert carbon dioxide into bicarbonate in plasma.
- D
Accessory muscles control the diffusion of oxygen across capillary walls.
09
Written response
1 point
Which brainstem structure generates the basic breathing rhythm?
10
Choose all
1 point
Select all conditions that tend to promote hemoglobin releasing more oxygen in body tissues.
- A
Oxygen availability is lower
- B
Oxygen availability is higher
- C
Carbon dioxide is higher
- D
Acidity is higher
- E
Temperature is lower
11
Choose one
1 point
Which description matches gas exchange between blood and body tissues?
- A
Oxygen moves from tissues into blood, and carbon dioxide moves from blood into tissues.
- B
Both oxygen and carbon dioxide move from blood into tissues.
- C
Oxygen moves from alveoli into blood, and carbon dioxide moves from blood into alveoli.
- D
Oxygen moves from blood into tissues, and carbon dioxide moves from tissues into blood.
12
Choose all
1 point
Select all accurate statements about how chemoreceptors influence breathing.
- A
Central chemoreceptors detect acidity changes in fluid surrounding the brain caused by CO₂.
- B
Central chemoreceptors primarily detect low oxygen in the alveoli.
- C
Peripheral chemoreceptors respond to changes in blood acidity.
- D
Peripheral chemoreceptors respond to oxygen changes and become especially important when arterial oxygen falls substantially.
- E
Peripheral chemoreceptors generate the basic breathing rhythm.
13
Open ended
1 point
Explain why alveolar ventilation is more directly relevant to gas exchange than the total amount of air moved into and out of the lungs. Include the role of anatomical dead space.
14
True or false
1 point
Voluntarily changing breathing for a time stops automatic breathing control from responding to the body's needs.
- A
True
- B
False
15
Choose one
1 point
During inhalation, which sequence explains why air flows into the lungs?
- A
The chest cavity contracts, raising lung pressure above atmospheric pressure.
- B
The chest cavity expands, lowering lung pressure below atmospheric pressure.
- C
The diaphragm relaxes, lowering lung pressure below atmospheric pressure.
- D
The lungs actively push air inward without a pressure difference.
16
Choose one
1 point
A change in breathing moves more air overall, but much of the increase remains in conducting airways. Which measure most directly indicates how much fresh air is available for gas exchange each minute?
- A
The total air moved in and out of the lungs, including air in the conducting airways.
- B
The amount of air exhaled during forced breathing only.
- C
The amount of fresh air reaching the alveoli each minute.
- D
The amount of oxygen carried by hemoglobin each minute.
17
Choose one
1 point
Incoming pulmonary capillary blood has less oxygen than the air in the alveoli. Which direction does oxygen diffuse, and why?
- A
Oxygen diffuses from alveolar air into the blood because its partial pressure is higher in the alveoli.
- B
Oxygen diffuses from the blood into the alveoli because its partial pressure is higher in the blood.
- C
Carbon dioxide diffuses from the alveoli into the blood because its partial pressure is higher in the alveoli.
- D
Neither gas moves unless the alveoli actively pump it across their walls.
18
Written response
1 point
What is the term for inhaled air that remains in the conducting airways instead of reaching gas-exchanging surfaces?
19
Choose one
1 point
An active tissue becomes warmer as its oxygen demand rises. Which change helps hemoglobin release more oxygen there?
- A
Lower carbon dioxide levels
- B
Lower acidity
- C
Lower tissue temperature
- D
Higher tissue temperature
20
Written response
1 point
The material identifies carbon dioxide, acidity, and one other condition as tending to be higher in tissues where hemoglobin releases more oxygen. What is that other condition?