Interactive Physiology
The Respiratory System: Gas Transport
Oxygen transport in the blood:
_98.5____% is bound to hemoglobin
_1.5____% dissolves in plasma
The hemoglobin molecule is composed of _4__ polypeptide chains and _4__ heme groups containing iron.
What does oxygen bind to? ___hemoglobin______
After one oxygen molecule (O2) binds to hemoglobin, it is easier for the other molecules to bind to the hemoglobin.
When oxygen is loaded onto hemoglobin in the lungs, hemoglobin is called __oxyhemoglobin_______________, and when oxygen is unloaded from the hemoglobin at the tissues it is called __deoxyhemoglobin__________________.
From the oxygen-hemoglobin dissociation curve, we see the following:
Lungs:
Partial pressure of oxygen is _100___ mmHg
Hemoglobin is _98___% saturated
Tissues:
Partial pressure of oxygen is 40___ mmHg
Hemoglobin is _75___% saturated
Effect of high altitude on lung PO2: 80mm Hg, hemoglobin 95% saturated
With a decrease of 20 mmHg in the lungs, will the saturation of hemoglobin decrease significantly? ____no_________
Effect of exercise on tissue PO2: lowers Po2 (20mm Hg)
With a decrease of 20 mmHg in the tissues, will the saturation of hemoglobin decrease significantly? _no_____.
Name the other factors that alter PO2: pH, temperature, Pco2, and BPG
During exercise,