Questions and All Correct Answers
2026 Updated.
GAS EXCHANGE - Answer
One of the functions of the cardiovascular
and respiratory systems is to rid the body
of CO2
. Where does the CO2
come from? - Answer CO2
is a breakdown product of the carbohydrates
oxidized in cellular respiration
The lungs are highly branched. What is
the primary purpose of this branching? - Answer It increases the surface
area of the lungs
-The alveoli account for volume
How do gases "know"
which way to flow? - Answer Gas flows from high to low partial pressure down a pressure
gradient
Rank the partial pressure of oxygen, nitrogen, and oxygen + nitrogen - Answer Oxygen <
Nitrogen < Nitrogen + Oxygen
When is the partial pressure of Oxygen higher?
-Leaving the tissue capillaries
-Entering the tissue capillaries - Answer The partial pressure of oxygen (pO2) is much higher
when entering the tissue because it has just gone through the heart
When is the partial pressure of oxygen higher?
-Leaving the alveoli capillaries of the lung
-Entering the alveoli capillaries of the lung - Answer The partial pressure of oxygen is higher
when leaving the alveoli of the lung and the pressure is lower when entering the alveoli of the
lung
,Inhaled air has _____ oxygen, and exhaled air has more ________ - Answer More; CO2
The _____ atrium flows deoxygenated blood to the lungs. - Answer Right
The ____ atrium flows oxygenated blood to the tissues - Answer Left
What is myoglobin? - Answer An oxygen-binding protein found in muscle cells. It is not found
in the blood
During heavy exercise,
skeletal muscles use more
oxygen and produce more
carbon dioxide than other
tissues like the liver. How
does this affect the
function of hemoglobin? - Answer PO2 saturation would be 100%
What is the Bohr Effect? - Answer Decreases in pH occur
-when CO2 is released from metabolizing cells
-When an inadequate supply of O2 is reduced
-More O2 is released and supplied to the cells for aerobic ATP synthesis
When pH falls during exercise - Answer H+ concentration increases and the affinity of
hemoglobin for O2 decreases, resulting in a rightward shift in the dissociation curve
How does blood pH at muscle tissue
compare to blood pH at the lungs? - Answer Blood pH is lower at the muscle
If carbonic anhydrase stopped working,
the amount of oxygen delivered to
systemic tissues would _________. - Answer Decrease. Carbonic anhydrase is blocked
meaning that H is not produced and none of it can be in the membrane, therefore the pH will go
up
, Is there a negative or positive correlation between P02 saturation and pH? - Answer Negative
correlation. As the PO2 saturation in a cell increases, the pH decreases
-Example - muscle cells
Hemoglobin versus myoglobin - Answer -Hemoglobin is essential for transferring oxygen in
your blood from the lungs to the tissues.
-Myoglobin, in muscle cells, accepts, stores, transports and releases oxygen.
What factors increase the affinity of hemoglobin to O2? - Answer Lower CO2
Higher pH
Lower temperature
What factors decrease the affinity of hemoglobin to O2? - Answer Higher CO2
Lower pH
Higher temperature
When the diaphragm contracts, the
volume of the lungs _____ - Answer Increases
When the diaphragm contracts, the pressure of the lungs ____ - Answer Decreases
Inhalation and pressure
Diaphragm contracts - Answer Air pressure is higher in the atmosphere than in lungs
-Diaphragm moves down
Exhalation and pressure
Diaphragm constrict - Answer Air pressure is higher in the lungs than in the atmosphere
-Diaphragm relaxes and moves up
Initiation of the heart contraction begins at - Answer the SA node
At high altitudes, the partial pressure
of oxygen is ______ the partial
pressure of oxygen at sea level. - Answer Lower than