Ch 24 CO2 Flashcards
(13 cards)
what produces carbon dioxide
mitochondria
3 methods of CO2 transport
- dissolved CO2 in plasma
- CO2 binding to Hb
- As bicarbonate ions
what is an important blood buffer
bicarbonate (HCO3-)
haldane effect
oxygenation = promotes CO2 unloading from blood
de oxygenation = promotes CO2 uptake by blood
CO2 transport at systemic tissues vs respiratory surface
systemic tissues
= CO2 enters blood and is mostly converted to HCO3- (bicarbonate) via carbonic anhydrase
- HCO3- goes into plasma as Cl moves into the red blood cell
respiratory surface
= HCO3- enters blood cell and Cl- goes into the plasma
- HCO3- is converted back to CO2 via carbonic anhydrase
- CO2 then enters respiratory surface (alveoli) to be exhaled
______ anahydrase is needed for CO2 transport
carbonic anahydrase (CA)
proton exchange in humans vs fish
humans
accumulation of CO2 in blood lowers pH so have to….
- eliminate H+ via urine
fish
- H+ in plasma is exchanged with Na from enviro via gill epithelium
acid base regulation in sharks
have specialized acid & base secreting cells
if HCO3- is retained in the body it binds with ____ and causes cells to be more _____ ? what about reverse
binds with H+, to be more alkaline
HCO3- is eliminated = more acidic
describe alkaline tide
when sharks consume prey it increases their H+ content in stomach to digest it
- for every H+ made a HCO3- is produced and enters the bloodstream, pH rises
- to restore balance use base secreting cells to pump HCO3- out and bring blood back to correct pH
acidosis vs alkalosis
acidosis = blood pH is lower than normal pH
alkalosis = blood pH is higher than normal pH
birds have a higher tolerance of high altitude hypoxia compared to mammals due to (3)
- unidirectional ventilation
- thin gas exchange surfaces
- cross current flow
what is the indicator for respiratory/ metabolic acidosis/alkalosis
respiratory = pCO2
metabolic = HCO3- & H+ concentration
