Uploaded by Jessie Arnold

A&P Notes week 8

Ventilation perfusion matching
 Decrease in ventilation
o Something blocking an airway could cause this
o Body responds by decreasing in perfusion by vasoconstriction
 Decrease in perfusion: decrease blood flow in certain part of lungs
o Air bubbles could cause this
o Body responds by decreasing ventilation by bronchoconstriction
 Increase in perfusion
o Vasodilation would be the body’s response
*Your body matches the ventilation and perfusion!
Gas Transport
 When oxygen binds to hemoglobin, it increases the affinity for more oxygen
to bind
 Partial pressure of oxygen is on the x axis
 % saturation of hemoglobin is on the y axis
 CO2 levels increase when you exercise as well as the H+ levels
 pH decreases when you exercise
 if glycolysis goes up, BPG goes up
o BPG binds to hemoglobin and reduces the affinity for oxygen to bind
 More oxygen unloads in systemic tissues
 In the systemic system, CO2 is going to be moved into the blood stream
o CO2 forms an acid (carbonic acid) that makes the blood more acidic
o The goal in the systemic is to load the CO2
 The body can keep this reaction proceeding forward by getting
rid of the product (HCO3-) (known as the chloride shift) and the
H+ binds with the hemoglobin (which causes O2 unloading)
 What is the goal in the lungs?
o Unload it out of the blood stream (breathe it out)
 Reverse happens in the lungs
o Hydrogen released from hemoglobin
o Hb will load oxygen
o Reverse chloride shift
 Hypoventilation: respiratory acidosis
 Hyperventilation: alkaline