Lecture 35+36

Question 1

what is the fractional concentration of oxygen and in dry air?
what is the partial pressure?

Answer 1

FC = 21 percent

partial pressure = 159.6 (160 mm Hg)

Question 2

equation for partial pressure in dry air?

Answer 2

PO2 = Pb x FO2

Question 3

what is the barometric pressure?

Answer 3

760 mm Hg

Question 4

equation of partial pressure in the trachea?

Answer 4

PIO2 = (Pb - PH2O) x FIO2

Question 5

what is the fractional concentration and partial pressure of oxygen in the trachea?

Answer 5

FC = 20%

PP = 150 mm Hg

Question 6

What is the FC and PP of oxygen in the alveoli

Answer 6

FC = 14%

PP = 102 mm Hg

Question 7

O2 and CO2 concentrations in arterial and venous blood?

Answer 7

O2:
arterial = 95 mm Hg
venous = 40 mm Hg

CO2:
A = 40 mm Hg
V = 46 mm Hg

Question 8

equation for minute ventilation?

Answer 8

VE = VT x F

VT = vital volume (500ml or 0.50L) 
F = breathing frequency

Question 9

Dead space?

Answer 9

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

Question 10

equation of alveolar ventilation

Answer 10

Va = (Vt x F) - (Vd - F)

Question 11

Fowler’s method

Answer 11

used to measure anatomical dead space

Question 12

Bohr method

Answer 12

measure physiological dead space

Vd / Vt = 1 - PeCO2 / PaCO2

Question 13

pH and HCO3 in systemic artery

Answer 13

pH = 7.35 - 7.45

HCO3 = 23-28 mEq/L

Question 14

what is more effective breathing faster or deeply breathing?

Answer 14

deep breathing!

much higher alveolar ventilation

Question 15

alveolar ventilation equation?

Answer 15

Va = VeCO2 x 0.863 / PaCO2

Va and PaCO2 are inversely related

Question 16

how is glucose moved into the RBC’s?

Answer 16

by facilitated diffusion via the glut-1 receptor

Question 17

glucokinase vs hexokinase?

Answer 17

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

Question 18

what steps of glycolysis use ATP?

Answer 18

glucokinase / hexokinase

PFK-1

Question 19

what favors lactate formation?

Answer 19

high levels of NADH

Question 20

what steps of glycolysis form ATP

Answer 20

Phosphoglycerate kinase

Pyruvate kinase

Question 21

The cori cycle?

Answer 21

lactate from cells are taken to the liver where it is converted back to glucose

gluconeogenesis

Question 22

what are the inhibitors of glycolysis

Answer 22

fluoride

inhibits the enzyme enolase

2-phosphoglycerate does not get converted to phosphoenolpyruvate

Question 23

importance of glycolysis for the RBC’s?

Answer 23

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)

Question 24

hexokinase deficiency?

Answer 24

leads to hemolytic anemia due to lack of ATP and imbalance of osmotic pressure

low levels of 2,3 BPG!

Question 25

pyruvate kinase deficiency

Answer 25

leads to hemolytic anemia due to lack of ATP and imbalance of osmotic pressure

high levels of 2,3 BPG

Question 26

PFK-1 is allosterically regulated

Answer 26

high levels of ATP inhibits this enzyme

low levels of ATP (high AMP) stimulates glycolysis