MODIFIED FROM HAPS RESOURCE BY ZAC KOHL 4/30/2019
DETERMINANTS OF BLOOD OXYGEN CONTENT
Model 1: Oxygen Binding to a Single Hemoglobin Molecule
Hemoglobin (Hb) is a large molecule consisting of four peptide chain subunits. Each peptide
contains a heme group with an iron molecule at the core. Each heme subunit can reversibly bind one
oxygen molecule and, interestingly, the bound/unbound state of each of the four hemes affect how
easy it is for new oxygen to be bound and bound oxygen to be released. The number of oxygen
molecules bound determine hemoglobin saturation, often expressed as 0 to 100%.
Saturated Hemoglobin Molecule
QUESTIONS:
1. How many oxygen molecules are bound when a hemoglobin molecule is completely saturated?
There are 4 oxygen molecules are bound.
2. How many oxygen molecules are bound when a hemoglobin molecule is 75% saturated?
There are 3 oxygen molecules are bound.
3. Assuming you started with the molecule in Model 1, how many molecules of oxygen would need
to be released in order for the hemoglobin to be 75% saturated?
You would need 1.
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, 4. The number of oxygen molecules bound to hemoglobin tends to fluctuate up and down.
(Discuss the following questions with your group, and then write your answer)
a) Where in the body does oxygen bind to hemoglobin?
Oxygen binds to hemoglobin molecules in the lungs, increasing the amount of bound in the
hemoglobin.
b) Where in the body are oxygen molecules released from hemoglobin?
Oxygen molecules are released from the hemoglobin when it travels through the capillary beds of
many tissues and organs of the body.
5. Is it possible for one hemoglobin molecule to be 82% saturated? Why or why not?
it is not possible, because one molecule can only be in the state of 100% saturated.
6. How many molecules of oxygen are carried on 100 molecules of hemoglobin if the hemoglobin
molecules are completely saturated?
100 x 4 = 400 … there are 400 that are completely saturated.
7. After passing through a capillary bed, those 100 molecules of hemoglobin become 75%
saturated with oxygen. How many molecules of oxygen were unloaded (released)?
There are 100 molecules being released.
Model 2: Hemoglobin (Hb) Values and Their Effect on Oxygen Carrying Capacity Hemoglobin is
found in very high numbers within red blood cells, and there are trillions of red blood cells in our
blood. Because dealing with such large numbers can be challenging, hemoglobin is typically
measured by mass (g) and oxygen is measured by volume (ml). The following table provides
information about common parameters used in calculating blood oxygen levels.
Parameter Normal value
Number of hemoglobin molecules per red blood cell 250 million molecules
Number of red blood cells per deciliter (dL) of blood (There are 10 500 billion cells
deciliters in 1 liter of blood)
Mass of hemoglobin in a deciliter (dL) of blood 15 grams (g)
Amount of oxygen 1 gram of hemoglobin can bind when 100% 1.34 milliliters (mL)
saturated
This study source was downloaded by 100000840546212 from CourseHero.com on 02-18-2022 13:32:26 GMT -06:00
https://www.coursehero.com/file/50551810/AP-HEMOGLOBIN-WSdocx/
DETERMINANTS OF BLOOD OXYGEN CONTENT
Model 1: Oxygen Binding to a Single Hemoglobin Molecule
Hemoglobin (Hb) is a large molecule consisting of four peptide chain subunits. Each peptide
contains a heme group with an iron molecule at the core. Each heme subunit can reversibly bind one
oxygen molecule and, interestingly, the bound/unbound state of each of the four hemes affect how
easy it is for new oxygen to be bound and bound oxygen to be released. The number of oxygen
molecules bound determine hemoglobin saturation, often expressed as 0 to 100%.
Saturated Hemoglobin Molecule
QUESTIONS:
1. How many oxygen molecules are bound when a hemoglobin molecule is completely saturated?
There are 4 oxygen molecules are bound.
2. How many oxygen molecules are bound when a hemoglobin molecule is 75% saturated?
There are 3 oxygen molecules are bound.
3. Assuming you started with the molecule in Model 1, how many molecules of oxygen would need
to be released in order for the hemoglobin to be 75% saturated?
You would need 1.
This study source was downloaded by 100000840546212 from CourseHero.com on 02-18-2022 13:32:26 GMT -06:00
https://www.coursehero.com/file/50551810/AP-HEMOGLOBIN-WSdocx/
, 4. The number of oxygen molecules bound to hemoglobin tends to fluctuate up and down.
(Discuss the following questions with your group, and then write your answer)
a) Where in the body does oxygen bind to hemoglobin?
Oxygen binds to hemoglobin molecules in the lungs, increasing the amount of bound in the
hemoglobin.
b) Where in the body are oxygen molecules released from hemoglobin?
Oxygen molecules are released from the hemoglobin when it travels through the capillary beds of
many tissues and organs of the body.
5. Is it possible for one hemoglobin molecule to be 82% saturated? Why or why not?
it is not possible, because one molecule can only be in the state of 100% saturated.
6. How many molecules of oxygen are carried on 100 molecules of hemoglobin if the hemoglobin
molecules are completely saturated?
100 x 4 = 400 … there are 400 that are completely saturated.
7. After passing through a capillary bed, those 100 molecules of hemoglobin become 75%
saturated with oxygen. How many molecules of oxygen were unloaded (released)?
There are 100 molecules being released.
Model 2: Hemoglobin (Hb) Values and Their Effect on Oxygen Carrying Capacity Hemoglobin is
found in very high numbers within red blood cells, and there are trillions of red blood cells in our
blood. Because dealing with such large numbers can be challenging, hemoglobin is typically
measured by mass (g) and oxygen is measured by volume (ml). The following table provides
information about common parameters used in calculating blood oxygen levels.
Parameter Normal value
Number of hemoglobin molecules per red blood cell 250 million molecules
Number of red blood cells per deciliter (dL) of blood (There are 10 500 billion cells
deciliters in 1 liter of blood)
Mass of hemoglobin in a deciliter (dL) of blood 15 grams (g)
Amount of oxygen 1 gram of hemoglobin can bind when 100% 1.34 milliliters (mL)
saturated
This study source was downloaded by 100000840546212 from CourseHero.com on 02-18-2022 13:32:26 GMT -06:00
https://www.coursehero.com/file/50551810/AP-HEMOGLOBIN-WSdocx/
