Include. 1  Supplement. 2  LIFEPAC Science Diagnostic Test, Grades 7-12. In Stock. 3  Lifepac Science Grade 10: Science Experiments on DVD. In Stock. 4  LIFEPAC Science Grade 10 Manipulatives Kit. In Stock. 5  Included in Kit. 6  Lifepac Science, Grade 10 (Biology), Teacher's Guide. In Stock. 7  Lifepac Science, Grade 10 (Biology), Workbook Set. In Stock.
I'm not sure what the mechanism is, but the nurse is only partially right. An increase in pCO2 causes vasoconstriction in the pulmonary vasculature and vasodilation EVERYWHERE else. CO2 causes constriction in the pulmonary vasculature because an increase in pC02 sends the message there is damage/shunting here, sending blood here will not effectively oxygenate it so blood is preferentially sent to a different part of the lung where it will receive better oxygenation.
Sympathetic innervation will cause vasoconstriction of vessels to GI organs and stuff you DON'T need during a sympathetic (fight or flight) response (in addition to increasing heart rate, etc.). Parasympathetic will cause vasodilation of these vessels, so lots of blood to GI organs during rest and digest.here be vasodilation, which has nothing to do with sympathetic stimulation, to muscle groups that you would be using during the flight or fight response. Those muscles are active and require oxygen and other metabolic needs at that time.