Lecture 35+36 Flashcards
what is the fractional concentration of oxygen and in dry air?
what is the partial pressure?
FC = 21 percent
partial pressure = 159.6 (160 mm Hg)
equation for partial pressure in dry air?
PO2 = Pb x FO2
what is the barometric pressure?
760 mm Hg
equation of partial pressure in the trachea?
PIO2 = (Pb - PH2O) x FIO2
what is the fractional concentration and partial pressure of oxygen in the trachea?
FC = 20%
PP = 150 mm Hg
What is the FC and PP of oxygen in the alveoli
FC = 14%
PP = 102 mm Hg
O2 and CO2 concentrations in arterial and venous blood?
O2:
arterial = 95 mm Hg
venous = 40 mm Hg
CO2:
A = 40 mm Hg
V = 46 mm Hg
equation for minute ventilation?
VE = VT x F
VT = vital volume (500ml or 0.50L) F = breathing frequency
Dead space?
anatomic dead space and alveolar dead space
this is a volume of air that does not participate in gas exchange
Vd / Vt = 0.25 - 0.35
equation of alveolar ventilation
Va = (Vt x F) - (Vd - F)
Fowler’s method
used to measure anatomical dead space
Bohr method
measure physiological dead space
Vd / Vt = 1 - PeCO2 / PaCO2
pH and HCO3 in systemic artery
pH = 7.35 - 7.45
HCO3 = 23-28 mEq/L
what is more effective breathing faster or deeply breathing?
deep breathing!
much higher alveolar ventilation
alveolar ventilation equation?
Va = VeCO2 x 0.863 / PaCO2
Va and PaCO2 are inversely related
how is glucose moved into the RBC’s?
by facilitated diffusion via the glut-1 receptor
glucokinase vs hexokinase?
glucokinase - found in the liver and pancreas
has a high Km for glucose (only when glucose levels are high)
hexokinase - found in all other tissues; low Km for glucose
what steps of glycolysis use ATP?
glucokinase / hexokinase
PFK-1
what favors lactate formation?
high levels of NADH
what steps of glycolysis form ATP
Phosphoglycerate kinase
Pyruvate kinase
The cori cycle?
lactate from cells are taken to the liver where it is converted back to glucose
gluconeogenesis
what are the inhibitors of glycolysis
fluoride
inhibits the enzyme enolase
2-phosphoglycerate does not get converted to phosphoenolpyruvate
importance of glycolysis for the RBC’s?
major source of energy for RBC’s
also forms 2,3 BPG! (decreases the affinity of hemoglobin for O2 in high amounts) (increased in those who live in high altitudes)
hexokinase deficiency?
leads to hemolytic anemia due to lack of ATP and imbalance of osmotic pressure
low levels of 2,3 BPG!
pyruvate kinase deficiency
leads to hemolytic anemia due to lack of ATP and imbalance of osmotic pressure
high levels of 2,3 BPG
PFK-1 is allosterically regulated
high levels of ATP inhibits this enzyme
low levels of ATP (high AMP) stimulates glycolysis
