5th Physiology Lecture Exam - Respiratory System (Batch 2024) Flashcards
1.At the start of inspiration, alveoli are kept open by ___ pressure;
A.Negative alveolar
B.Negative trans airway
C.Positive intrapleural
D.Positive transpulmonary
D.Positive transpulmonary
2.At high altitude, affinity of hemoglobin to oxygen decreases when there is INCREASED blood;
A.2,3 – diphosphoglycerate
B.CO2 pressure
C.O2 pressure
D.pH
A.2,3 – diphosphoglycerate
3.A diver who breathes gas mixture of 50% O2, 50% Helium and works underwater where atmospheric 4 times the normal will experience one of these as he ascends to surface:
A.Apnea
B.Bends (or decompression sickness)
C.Nitrogen narcosis
D. O2 toxicity
B.Bends (or decompression sickness)
4.The volume of air in the lungs at the end of normal expiration is:
A.Expiratory reserve volume
B.Functional residual capacity
C.Inspiratory capacity
D.Residual volume
B.Functional residual capacity
5.The largest possible tidal volume is:
A.Functional residual capacity
B.Inspiratory capacity
C.Total lung capacity
D.Vital capacity
D.Vital capacity
6.A reduction in one of these DECREASES O2 content of inspired air:
A.Altitude
B.Atmospheric pressure
C.Pleural pressure
D.Surfactant
B.Atmospheric pressure
- Central chemoreceptors are strongly stimulated by INCREASED arterial:
A. CO2 pressure
B. O2 pressure
C. pH
D. All of these
A. CO2 pressure
- Pulmonary edema will occur in one of these conditions:
A. Prolonged stay in outer space
B. Prolonged stay in deep sea
C. Rapid ascent to high altitude
D. Rapid descent to deep sea
C. Rapid ascent to high altitude
- Effect of centrifugal acceleratory force in the body includes:
A. Decreased bone mass
B. Decreased cardiac output
C. Increased diffusing capacity
D. Increased stroke volume
B. Decreased cardiac output
- Narcosis associated with deep sea diving is due to:
A. Damage of cellular metabolic systems
B. Depression of respiratory center
C. Formation of gas bubbles
D. Reduction in membrane excitability
D. Reduction in membrane excitability
- Mechanism of cerebral edema in acute mountain sickness is:
A. Reduction of blood pressure
B. Reduction of red blood cell mass
C. Vasodilation of cerebral vessels
D. Vasodilation of systemic vessels
C. Vasodilation of cerebral vessels
- Air embolism associated with deep sea diving is due to
A. Breath-holding during acsent
B. Breath-holding during descent
C. Rapid ascent to deep sea
D. Rapid ascent to surface
A. Breath-holding during acsent
- The reduction in lung volume during forceful expiration
is primarily due to:
A. Contraction of expiratory muscles
B. Elastance of chest wall
C. Elevation of alveolar pressure
D. Resistance of airways
E.
A. Contraction of expiratory muscles
- Physiologic effect of surface tension on lung is to:
A. Decrease forces that tend to collapse lungs
B. Decrease work to expand alveoli with each
breath
C. Increase (distending) pressure to keep lungs
Collapsed
D. Increase resistance of lungs to expand
D. Increase resistance of lungs to expand
- A reduction in of these DECREASES lung compliance
A. Alveolar ventilation
B. Pulmonary perfusion
C. Surfactant concentration
D. Transpulmonary pressure
C. Surfactant concentration
- The action of external intercostal muscles is to:
A. Elevate the rib cage
B. Lift the lungs upward
C. Pulls rib downward and inward
D. Push diaphragm upward
A. Elevate the rib cage
- The basic rhythm of respiration is due to:
A. Communication between neurons in pons
and medulla oblongata
B. Control neurons in medulla oblongata
C. Discharge of impulses from pontine neurons
D. Modulation of higher brain centers
B. Control neurons in medulla oblongata
- Which of these is a physiologic response to rapid
ascent to high altitude?
A. Decreased minute ventilation
B. Decreased pulmonary vascular resistance
C. Increased diffusing capacity
D. Increased tubular reabsorption of HCO3-
C. Increased diffusing capacity
- Effect of O2 toxicity associated with deep sea diving is:
A. Alveolar collapse due to loss of
surfactant
B. Apnea due to depression of respiratory
center
C. Convulsions due to decreased membrane excitability
D. Muscle paralysis due to formation of O2 bubbles
C. Convulsions due to decreased membrane excitability
- Mechanism of decompression sickness in deep sea
diving is:
A. Gas molecules dissolved in fat during
sudden ascent
B. Gas bubbles formed during sudden
ascent
C. Lung expansion during sudden descent
D. Respiratory inhibition during prolonged stay
beneath sea
B. Gas bubbles formed during sudden
ascent
- Effect of severe hypercapnia associated with deep sea
diving is:
A. Apnea
B. Atelectasis
C. Barotrauma
D. Chokes
A. Apnea
- The change in diffusing capacity during rapid ascent to
high altitude is due to INCREASED:
A. Arterial O2 pressure
B. Blood viscosity
C. Systemic blood pressure
D. Total lung capacity
D. Total lung capacity
- Effect of rapid ascent to high altitude on PaCO2 is
primarily due to:
A. Decreased airway resistance
B. Decreased cellular metabolism
C. Increased alveolar ventilation
D. Increased diffusing capacity
C. Increased alveolar ventilation
- Chronic mountain sickness is associated with
DECREASED:
A. Left ventricular diameter
B. Peripheral arterial pressure
C. Pulmonary arterial pressure
D. Red blood cell mass
B. Peripheral arterial pressure
- Use of helium in deep sea dives is preferred to
nitrogen because HELIUM:
A. Diffuse rapidly out of tissues
B. Dissolves rapidly in blood
C. Possesses greater density
D. All of these
A. Diffuse rapidly out of tissues
- During inspiration pleural pressure becomes:
A. Equal to alveolar pressure due to increased
lung volume
B. Less negative due to chest wall expansion
C. More negative due to increased elastic
recoil of lungs
D. Zero due to opposing elastic recoil o lungs
and chest wall
C. More negative due to increased elastic
recoil of lungs
- Pleural pressure at the end of expiration is due to:
A. Compliance of chest wall
B. Compliance of lungs
C. Outward recoil of chest wall
D. Outward recoil of lungs
D. Outward recoil of lungs
- Physiologic importance of surfactant is to DECREASE:
A. Compliance of lungs
B. Elastic recoil of lungs and chest wall
C. Resistance of airways
D. Surface tension of alveolar fluid
D. Surface tension of alveolar fluid
- DECREASED inspiratory reserve volume
DECREASES:
A. Expiratory reserve volume
B. Functional residual capacity
C. Inspiratory capacity
D. Tidal volume
C. Inspiratory capacity
- Increased expiratory reserve volume will INCREASE:
A. Functional residual capacity
B. Inspiratory capacity
C. Residual volume
D. Tidal volume
A. Functional residual capacity
- Work of breathing INCREASED when there is
DECREASED:
A. Airway resistance
B. Atmospheric pressure
C. Lung compliance
D. Transpulmonary pressure
C. Lung compliance
- The primary determinant of airway resistance is:
A. Length of airway
B. Radius of airway
C. Temperature of air
D. Viscosity of air
B. Radius of airway
- Characteristic feature of alveolar epithelium that
enhanced diffusion of gases is:
A. Large diffusion distance
B. Large surface area
C. Thick respiratory membrane
D. Thick surfactant layer
B. Large surface area
- Role of respiratory neurons in medulla during quiet
breathing is to:
A. Activate expiratory neurons of ventral
respiratory group (VRG)
B. Activated inspiratory neurons of dorsal
respiratory group (DRG)
C. Inhibit expiratory neurons of VRG
D. Inhibit inspiratory neurons of DRG
B. Activated inspiratory neurons of dorsal
respiratory group (DRG)
- Physiologic role of pneumotaxic center in upper pons
is to:
A. Decrease duration of expiration by
stimulating DRG
B. Increase respiratory rate by limiting
duration of inspiration
C. Modulate activity of inspiratory neurons by
gas blood values
D. Terminate inspiration by inhibiting DRG
B. Increase respiratory rate by limiting
duration of inspiration
- Respiratory rate increases when there is INCREASED:
A. Duration of expiration
B. Duration of inspiration
C. Expiratory time
D. Ramp signal
D. Ramp signal
- Effect of hypoxemia on respiratory center is:
A. Inhibition due to inhibition of central
chemoreceptors
B. Inhibition due to inhibition of peripheral
chemoreceptors
C. Stimulation due to activation of central
chemoreceptors
D. Stimulation due to activation of
peripheral chemoreceptors
D. Stimulation due to activation of
peripheral chemoreceptors
- Which of these will have greater effect on central
chemoreceptors?
A. Acute hypercapnea
B. Chronic hypercapnea
C. Acute hypoxemia
D. Chronic hypoxemia
B. Chronic hypercapnea
- Peripheral chemoreceptors are strongly stimulated by
LOW:
A. Arterial pH
B. PaCO2
C. PaO2
D. All of these
C. PaO2
- Physiologic unit of respiratory system consists of:
A. Lobar bronchi, non-respiratory bronchioles
B. Respiratory bronchioles, alveolar ducts
C. Segmental bronchi, terminal bronchioles
D. Trachea, bronchi
B. Respiratory bronchioles, alveolar ducts