The diffusion of atmospheric o2 from the alveoli of the lungs to the blood in the pulmonary capillaries. In exchange CO2 in blood coming from tissues diffuses into alveolar capillaries and is exhaled....
External Respiration. For gas to pass from alveolar space into blood it must:
1. cross the membrane and cytoplasm of the very thin ____.
2. then through the basement membrane of the ____.
3. then through the basement membrane of the ____.
4. across the membrane and cytoplasm of the very thin ____.
1. type I alveolar cell.
2. type I alveolar cell.
3. endothelial cell.
4. endothelial cell lining of the capillary.
basements are fused
The amount of air (in liters) entering the lungs each minute.
The amount of air entering the alveoli each min. If air enters lungs but not alveoli, it cant be absorbed into blood.
The amount of blood that flows through the lung capillaries each min.
Under hypoxic conditions (low amounts of o2)
pulmonary blood vessels do what? This causes blood to to move to area of
high o2. This matching of pulmonary blood flow to oxygen is called ____
The exchange of O2 and CO2 between systemic capillaries and tissue cells.
The partial pressure of O2 is ___ in the tissue and __ in the blood so it diffuses in to the tissue.
Almost all of the oxygen is carried by ____.
Hgb picks up O2 where the concentration (partial pressure) is ___ and releases O2 where concentration is lowest.
What has the highest partial pressure of O2. What has the lowest?
98.5% of O2 is bound to ___ in RBC. 1.5% of O2 is dissolved in the ___.
70% of CO2 travels through the blood stream as _____. 23% of CO2 is bound to ____. 7% is dissolved in the ____.
What has the highest partial pressure of CO2. What has the lowest?
Most of the CO2 is carried by ____.
Obj 15. see pg 847-848
Actively working tissues generate acids as waste which do what to pH.
A drop in pH shifts the saturation curve to the ___, causing more O2 to be released into the tissues.
right (towards Y axis)
If pH is higher, hgb affinity curve shifts to the ___ causing more O2 to be bound at the ___ instead of the tissues.
If PCO2 is higher, hgb affinity curve shifts to the ___ meaning less O2 bound at ___.
lung, more O2 delivered to tissues.
If PCO2 is lower, hgb affinity curve shifts to the ___, meaning more O2 bound at ___ and less at ___.
Higher temp shifts curve to the ____. Meaning more O2 to ___.
Lower temps shifts curve to the ___. Meaning more O2 ___.