CO2 transport

Question 1

What is the role of CO2 in acid-base balance?

Answer 1

pH determined by ratio of carbon dioxide to bicarbonate in the blood - increased CO2 = low (acidic) pH

Question 2

Define acid

Answer 2

Any chemical that can donate a proton (H+)

Question 3

Define base

Answer 3

Any chemical that can accept a proton (H+)

Question 4

Define buffer

Answer 4

Temporarily ‘mop up’ Hydrogen ions to restore pH balance when necessary

Question 5

Define pH

Answer 5

The concentration of Hydrogen ions in a solution (inverse relationship between pH and H+ so as the concentration of H+ goes up, pH goes down)

Question 6

Define pK

Answer 6

Ratio of the concentrations of dissociated and undissociated weak acids
Is a constant in the Henderson-Hasselbalch equation (pK = 6.1)

Question 7

What are the common buffer systems in humans?

Answer 7

Respiratory - if pH is low, H+ react with HCO3- and release CO2 which is expired

Renal - if pCO2 is high, kidneys excrete less HCO3- to restore pH

Question 8

What is the role of Carbonic Dehydratase (Carbonic Anydrase) in humans?

Answer 8

Acts as a catalyst for the breakdown of Carbonic Acid into water and carbon dioxide

Question 9

How is CO2 transported in blood?

Answer 9

Dissolved
As carbamino compounds
As bicarbonate (main mechanism of transport)