Respiratory practice quiz Flashcards
Which structure is found in the respiratory zone of the lungs
- bronchioles
- terminal branches
- bronchi
- respiratory bronchioles
D
If small particles are able to enter the airways, they will be captured by?
Mucus
T/F: the respitatory bronchioles are transioltional structures between the conducting and respiratory zones of the lungs. Because they are transitional , they constrain cilia, smooth muscle, and alveoli
True
T/F: exchange of gasses across an alveolus is efficient because of a large surface area and thin alveolar walls
True
T/F: pulmonary blood flow is distributed evenly in the lungs
False
T/F: tidal volume is defined as normal, quite breathing and involves inspiration and expiration of air
True
The additional volume that can be inspired above tidal volume is called?
- expiratory reserve volume
- inspiration reserve volume
- residual volume
Inspiration reserve volume
The volume of gas remaining in the lungs after a maximal forced expiration is called
Residual volume
Tidal volume plus inspiratory reserve volume is the:
a. Inspiratory capacity
b. Functional residual capacity
c. Vital capacity
d. Total lung capacity
A
Inspiratory capacity plus the expiratory reserve volume is the:
a. Inspiratory capacity
b. Functional residual capacity
c. Vital capacity
d. Total lung capacity
C
Anatomic dead space includes the volume of the conducting airways, but not the
respiratory bronchioles and alveoli. True or false?
true
It is never possible for the physiologic dead space to be larger than the anatomic dead
space. True or false?
Arterial PCO2 (PaCO2) always equals alveolar PCO2 (PACO2) in a situation with constant CO2
production. True or false?
t
Air flows into the lungs because this/these important muscle(s) contracts, ultimately
increasing intrathoracic volume and lowering intrathoracic pressure:
a. External intercostal muscles
b. Accessory muscles
c. Internal intercostal muscles
d. Diaphragm
D
As intrapleural pressure becomes negative, what happens to the lungs?
a. No change
b. Deflate
c. Inflate
C
Compliance is a measure of how volume changes as a result of a pressure change and
for the lungs, this is demonstrated in a pressure-volume loop. True or false?
t
When the volume of the airways is equal to the functional residual capacity (FRC), the
airway pressure will be zero. Additionally, the collapsing force on the lungs is equal to
the expanding force on the chest wall at FRC. True or false?
t
Emphysema is associated with a loss of elastic fibers in the lungs and as a result,
compliance will:
a. Increase
b. Decrease
c. Not change
A
Emphysema requires higher lung volumes in order to establish a higher FRC (to reach an
airway pressure of zero). True or false?
t
Small alveoli have high collapsing pressures due to their size and surface tension.
Surfactant is produced by Type I alveolar cells, reduces surface tension and decreases
lung compliance. True or false?
Where is the site of highest airway resistance?
a. Small bronchi
b. Medium bronchi
c. Large bronchi
B
Stimulation of parasympathetic receptors on bronchial smooth muscle will decrease
airway diameter, constriction smooth muscle and decrease airflow resistance. True or
false?
There is an expanding pressure on the lungs when the transmural pressure (pressure
across the lungs) is:
a. Zero
b. Negative
c. Positive
C
Intrapleural pressure will become more ________________ during inspiration as
compared to rest.
a. Negative
b. Positive
A
The partial pressure difference of a gas across a membrane will drive it to diffuse across,
not the concentration difference of the gas. True or false?
t
Bicarbonate is a form of carbon dioxide and is considered to be a:
a. Dissolved gas
b. Chemically modified gas
c. Bound gas
B
The PO2 of humidified tracheal air is approximately:
a. 100 mm Hg
b. 40 mm Hg
c. 160 mm Hg
d. 150 mm Hg
D
The PAO2 of alveolar air is approximately:
a. 100 mm Hg
b. 40 mm Hg
c. 160 mm Hg
d. 150 mm Hg
A
Blood leaving the pulmonary capillaries usually has the same PO2 and PCO2 as the alveolar
air. True or false?
t
If the total amount of gas transported across the alveolar/capillary barrier is limited by
blood flow through the pulmonary capillaries, this is referred to as:
a. Diffusion-limited gas exchange
b. Perfusion-limited gas exchange
B
Oxygen transport is perfusion-limited in the following condition:
a. Fibrosis
b. Exercise
c. Homeostasis
C
In perfusion-limited oxygen transport, PAO2 becomes equal to PaO2 about one third of the
distance along the capillary, so unless blood flow increases, no more oxygen can diffuse
into the capillary. True or false?
t
While dissolved oxygen that is free in solution accounts for only 2% of total oxygen
content in blood, dissolved oxygen is the only form of oxygen that produces a partial
pressure. True or false?
t
The oxygen-hemoglobin dissociation curve demonstrates that percent saturation of
hemoglobin is a function of the PO2 of the alveoli. True or false?
The steep slope of the sigmoidal oxygen-hemoglobin dissociation curve is due to the
_______________________________________ as each successive oxygen molecule
binds one of four heme groups in hemoglobin.
a. Increase in number of heme groups
b. Decrease in number of heme groups
c. Change in affinity of the heme groups for oxygen
C
P50 is the PO2 at which hemoglobin is:
a. 25% saturated
b. 50% saturated
c. 75% saturated
d. 100% saturated
B
When PO2 is highest (as in arterial blood), the affinity of hemoglobin for oxygen will be
high. True or false?
t
At a PO2 of _______________, hemoglobin will begin to rapidly desaturate.
a. 40 mm Hg
b. 60 mm Hg
c. 80 mm Hg
d. 100 mm Hg
B
What physiological condition will cause the oxygen-hemoglobin dissociation curve to
shift to the right (hemoglobin has decreased affinity for oxygen)?
a. Increase in pH
b. Decrease in PCO2
c. Decrease in temperature
d. Increase in 2,3-DPG
D
Carbon monoxide has a high affinity for hemoglobin and will bind at very low partial
pressures. True or false?
t
Erythropoietin (EPO) synthesis is induced in response to hypoxia. True or false?
t
The quantitatively important form of carbon dioxide in blood is:
a. Dissolved CO2
b. Carbaminohemoglobin
c. Bicarbonate
d. Carbonic acid
C
When CO2 binds hemoglobin, it binds in the same site where oxygen normally binds.
True or false?
As oxygen dissociates from hemoglobin in tissues, hemoglobin’s affinity for oxygen is
lowered. In turn, the affinity of hemoglobin for CO2 increases. True or false?
t
The major factor regulating pulmonary blood flow is:
a. PAO2
b. PaO2
c. PACO2
d. PaCO2
A
Hypoxemia always occurs in a:
a. Physiologic shunt
b. Left-to-right shunt
c. Right-to-left shunt
C
The normal, average value for V/Q ratio is:
a. 1
b. 0.8
c. 0.6
d. 0.4
B
In a V/Q mismatch where the ratio is low, ventilation is:
a. Normal
b. High
c. Low
C
The inspiratory center of the brain is located in the:
a. Apneustic center
b. Pneumotaxic center
c. Cerebral cortex
d. Medullary respiratory center
D
Brain stem chemoreceptors are very sensitive to pH of CSF and an increase in pH will
cause hyperventilation. True or false?
Once arterial PO2 falls below 60 mm Hg, peripheral chemoreceptors will respond to
stimulate an increase in breathing rate. True or false?
t
Hyperventilating at high altitudes will cause extra CO2 to be expired, thus decreasing
arterial PCO2 and causing:
a. Respiratory alkalosis
b. Respiratory acidosis
c. No change
A
Hypoxemia is defined as a decrease in O2 delivery to tissues. True or false?
This breathing pattern is common during anesthesia and heavy sedation and is irregular
with long apneic periods:
a. Cheyne-Stokes
b. Kussmaul’s
c. Biot’s
d. Apneustic
C
What is the partial pressure (mm Hg) of oxygen in a gas mixture containing 40% oxygen
if the barometric pressure is 300 mm Hg?
120 mm Hg (300 mm Hg x 0.4 = 120 mm Hg)
Define the term atelectasis.
PARTIAL OR COMPLETE COLLAPSE OF THE LUNG AND RESULTS WHEN THE CHEST WALL IS PIERCED
