Section 9 Flashcards
What does the direction O2 and CO2 diffuse across the alveoli-pulmonary capillary interface depend on?
The partial pressures of the gases
The pulmonary artery carries [oxygenated/deoxygenated] blood.
Deoxygenated
Is O2 or CO2 more soluble in the blood?
CO2
Changes in __________ causes the movement of the air
Intrapulmonary pressures
Contraction of the ______ increases the neck to abdomen size of the thoracic cage.
Diaphragm m.
Contraction of the ______ increases the anterior to posterior site of the thoracic cage
External intercostal m.s
A passive process because elastic potential energy is stored during inspiration in the lungs and thorax wall.
Resting expiration
_________ is caused by abdominal and internal intercostal muscle contraction decreasing thorax size.
Exercise expiration
The volume inspired or expired per breath; resting value 400-500 mL; increases during exercise
Tidal volume (Vt)
The volume remaining at the end of maximal expiration; resting value 1200 mL; slight decrease during exercise
Risidual volume (RV)
the maximal volume expired from end-expiration (following expiration phase normal breath); resting value is 1200mL; decrease during exercise
Expiratory Reserve Volume (ERV)
The maximal volume inspired from end-inspiration (following inspiration phase normal breath); Resting value: 3100 mL; decreases during exercise
Inspiratory Reserve Volume (IRV)
ERV + RV; decreases with exercises
Functional residual capacity (FRC)
IRV +Vt, or the maximal volume inspired from the resting expiatory level; resting value is 3500mL; increases with exercise
Inspiratory Capacity (IC)
The IC + FRC or the volume in the lung at the end of maximal inspiration; resting value is 6000 mL; slightly decreases with exercise
Total lung capacity (TLC)
The IRV + ERV or maximal volume forcefully expired after maximal inspiration; resting value 4800 mL; light decrease with exercise
Vital capacity (Vc)
The amount of air (L) that is either inspired or expired in one minute; usually refers to expired air
Minute ventilation (Ve)
Ve can be expressed in terms of ______.
Vt x F (breaths per minute)
What happens to Ve with exercise and increased work load?
Increases
Before exercise, what stimulates an increase in minute ventilation?
Nerve stimuli creates an anticipatory rise
Slower rise in ________ exercise levels off to a steady-state value.
Submaximal
True or false
Slower rise during progressive exercise does not level off but continues to rise until exercise ceases.
True
With sub maximal exercise, VO2 and Ve have a(n) [direct/inverse] and [proportional/in-proportional] relationship.
direct; proportional
SO, as VO2 increases, Ve increases at the same rate; relationship is linear
As max VO2 is approached, the linear relationship is lost. VO2 increases ______ and Ve increases ______
Slightly; large
How do untrained vs trained individuals compare to each other in order to produce the same amount of O2 or CO2?
Untrained individuals must work harder (they have a higher Ve)
What happens when the body is unable to take in enough oxygen?
The ETC shuts down so pyruvate builds up and is turned into lactate, which is then converted to H+, resulting in an acidic body pH
How does a normal person’s ventilation efficiency ratio (VO2/Ve and VCO2/Ve) compare to a deconditioned ventilation efficiency?
The ratio is smaller, indicating less oxygen efficiency
A reconditioned patient has to ventilate more air to….
consume the same amount of O2 or produce the same amount of CO2 as a conditioned patient
The portion of fresh air that reaches the alveoli and participates in gas exchange
Alveolar ventilation (Va)
The volume of fresh air that does not participate in gas exchange
Dead space (Vd)
During exercise Vd can double during exercise due to __________, but ________ also increases to maintain Va
dilation of the airways; Vt (tidal volume)
Vt
Tidal volume
RV
Residual volume
ERV
Expiratory Reserve Volume
IRV
Inspiratory Reserve Volume
FRC
Functional Residual Capacity
IC
Inspiratory Capacity
TLC
Total Lung Capacity
Vc
Vital Capacity
Ve
Minute Ventilation
Va
Alveolar ventilation
Vd
Dead space ventilation
The nonlinear increase in blood lactate during exercise or the onset of blood lactate accumulation
Lactate threshold
The exercise VO2 above which energy production from anaerobic glycolysis accelerates supplementing aerobic energy production
Anaerobic threshold; some think lactate accumulation is a sign of this
Lactic Acid + HCO3- –>
H20 + CO2 +NaLactate
Lactic acid is buffered by ________ buffer system yielding an increase in ______ production at the lungs
Bicarbonate; CO2
Blood pH [increases/decreases] with increased Va
Increases; pH controlled partially by respiratory compensation
In terms of lactate threshold, what is the difference between untrained individuals and trained individuals?
Trained individuals can use O2 more efficiently, so they can saturate the system with O2 to prevent lactate buildup
As you move to max work load, ___________ takes precedence of ver taking in O2
The need to expire CO2
At sub maximal workload (both at the same workload level), both trained and untrained individuals are moving the same VO2, but trained individuals are more efficient in moving O2. How do their Ve’s compare?
Untrained individuals have a higher Ve; trained individuals can move less air to consume the same amount of O2
