Carriage of CO2 (PK7)

Question 1

Waste products of metabolism

Answer 1

• 0.16g H2O/min
• 1.22kcal heat/min
• 200ml CO2/min

Question 2

3 ways CO2 is carried in blood, and what percentage is each of the total?

Answer 2

• Physically dissolved (5%)
• Bound to proteins as carbamino compounds (5%)
• Bicarbonate ions (90%)

Question 3

Equation of CO2 forming carbamino compounds

Answer 3

R-NH2 + CO2 –> R-NHCOOH <–> R-NHCOO- + H+

Question 4

What is the Haldane effect?

Answer 4

Deoxy Hb binds more CO2 than oxy Hb

Question 5

Equation of CO2 forming bicarbonate ions

Answer 5

CO2 + H2O <–> H2CO3 <–> HCO3- + H+

Question 6

Which step of CO2 forming bicarbonate ions is catalysed by an enzyme, and what is the enzyme?

Answer 6

• CO2 + H2O –> H2CO3
• Carbonic anhydrase