Gas Exchange: CO2 transport

Question 1

CO2 diffuses from ____ onto ____

Answer 1

CO2 diffuses from muscle onto RBCs

Question 2

Where does the CO2 go?

Answer 2

-5% gets dissolved in solution (PCO2) which is important for monitoring ventilation
-5% carried by Hb, called “carboaminohemoglobin”
-remaining CO2 gets converted into H+ and bicarbomate (HCO3)

Question 3

What does bicarbonate (HCO3) bind to for transport to lungs?

Answer 3

HCO3 binds to hemoglobin for transport to lungs

Question 4

why is H+ being buffered important?

Answer 4

it helps maintain the acid-base balance in blood

Question 5

in lungs whats the reaction (its reversed in lungs)

Answer 5

H+ and HCO3= CO2 and H2O

Question 6

what are the ventilation centers in the brain (feedfoward system)

Answer 6

the medulla oblongata and pons

Question 7

What are the ventilation centers responsible for?

SNS and PSNS?

Answer 7

Antinicipatory rise in VE

SNS signals bronchodialation to increase airflow

PSNS elicitis bronchoconstriction to decrease airflow

Question 8

What receptors in the peripheray muscles dictate sudden drops or rises in ventaltion?

Answer 8

Mechanoreceptors due to increase or absense of muscle contraction

Question 9

What receptors in the vessles dictate gradual increase/decrease in Ve?

Answer 9

chemoreceptors

Question 10

What is the main feedback variable used to dictate VE?

Answer 10

PCO2