WCU PHYS 261 Final Exam Questions
and Answers Graded A+
internal respiration and external respiration - Correct answer-What are the 2 types
of respiration?
from a high area to a low area - Correct answer-In which direction does air flow
due to pressure differences?
Gas exchange that occurs between the aleveoli and RBCs, and between the RBCs
and tissue - Correct answer-What is internal respiration?
air movement between the lungs and the atmosphere - Correct answer-What is
external respiration?
when air moves from the atmosphere into the lungs - Correct answer-What is
inhalation?
when air moves from the lungs into the atmosphere - Correct answer-What is
exhalation?
that pressure and volume are inversely proportional - Correct answer-What is
Boyle's Law?
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,760 mmHg - Correct answer-What is the atmospheric pressure at sea level?
pressure inside the lungs - Correct answer-What is intrapulmonary pressure?
volume inside the lungs - Correct answer-What is intrapulmonary volume?
760mmHg - Correct answer-What is the atmospheric pressure and intrapulmonary
pressure when you are at rest?(neither inhaling or exhaling)
400ml air - Correct answer-What is the lung volume during rest?
lower - Correct answer-For inspiration, is the intrapulmonary pressure higher or
lower than the atmospheric pressure?
-blood O2 levels are low, while CO2 is high
-chemoreceptors get stimulated
-chemoreceptors stimulate medulla(respiratory center)
-medulla stimulates the phrenic nerve
-phrenic nerve stimulates the diaphragm and respiratory muscles
-diaphragm and muscles move down and outward
-negative pressure created inside the lungs
-thoracic veins drain blood into the lungs
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, -increase in intrapulmonary volume
-decrease in intrapulmonary pressure by 4mmHg= 756mmHg
-air enters lungs - Correct answer-What are the steps of inspiration?
Central receptors
-located near the medulla
-detect hydrogen concentration in CSF and by detecting hydrogen, it can tell if
CO2 has increased
Peripheral receptors
-found in carotid artery and aortic bodies
-detects a decrease in O2 levels, and if decreased, it stimulates the medulla -
Correct answer-What are the 2 types of chemoreceptors and their functions?
-inhalation caused the lungs to be filled with air
-stimulates stretch receptors within the medulla
-medulla inhibits the phrenic nerve
-diaphragm and respiratory muscles no longer stimulated by phrenic nerve
-diaphragm and muscles relax
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and Answers Graded A+
internal respiration and external respiration - Correct answer-What are the 2 types
of respiration?
from a high area to a low area - Correct answer-In which direction does air flow
due to pressure differences?
Gas exchange that occurs between the aleveoli and RBCs, and between the RBCs
and tissue - Correct answer-What is internal respiration?
air movement between the lungs and the atmosphere - Correct answer-What is
external respiration?
when air moves from the atmosphere into the lungs - Correct answer-What is
inhalation?
when air moves from the lungs into the atmosphere - Correct answer-What is
exhalation?
that pressure and volume are inversely proportional - Correct answer-What is
Boyle's Law?
©COPYRIGHT 2025, ALL RIGHTS RESERVED 1
,760 mmHg - Correct answer-What is the atmospheric pressure at sea level?
pressure inside the lungs - Correct answer-What is intrapulmonary pressure?
volume inside the lungs - Correct answer-What is intrapulmonary volume?
760mmHg - Correct answer-What is the atmospheric pressure and intrapulmonary
pressure when you are at rest?(neither inhaling or exhaling)
400ml air - Correct answer-What is the lung volume during rest?
lower - Correct answer-For inspiration, is the intrapulmonary pressure higher or
lower than the atmospheric pressure?
-blood O2 levels are low, while CO2 is high
-chemoreceptors get stimulated
-chemoreceptors stimulate medulla(respiratory center)
-medulla stimulates the phrenic nerve
-phrenic nerve stimulates the diaphragm and respiratory muscles
-diaphragm and muscles move down and outward
-negative pressure created inside the lungs
-thoracic veins drain blood into the lungs
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
, -increase in intrapulmonary volume
-decrease in intrapulmonary pressure by 4mmHg= 756mmHg
-air enters lungs - Correct answer-What are the steps of inspiration?
Central receptors
-located near the medulla
-detect hydrogen concentration in CSF and by detecting hydrogen, it can tell if
CO2 has increased
Peripheral receptors
-found in carotid artery and aortic bodies
-detects a decrease in O2 levels, and if decreased, it stimulates the medulla -
Correct answer-What are the 2 types of chemoreceptors and their functions?
-inhalation caused the lungs to be filled with air
-stimulates stretch receptors within the medulla
-medulla inhibits the phrenic nerve
-diaphragm and respiratory muscles no longer stimulated by phrenic nerve
-diaphragm and muscles relax
©COPYRIGHT 2025, ALL RIGHTS RESERVED 3
