respiratory system 2

Question 1

explain the concentration and movement of O2 and CO2 between air, lungs, the blood and tissues? (Ficks, Daltons and Henry’s laws)

Answer 1

exchange of O2 and CO2 via passive diffusion
ficks law
- diffusion proportional to surface area, [ ] gradient and permeability.
- inversely proportional to distance

daltons
- each gas in a mixture exerts own pressure, proportional to [ ] in mixture

henrys
- quantity of gas that dissolves in liquid proportional to partial pressure and solubility coefficient of gas or liquid

Question 2

explain the steps to how O2 and CO2 are able to be transported in blood?

Answer 2

1. blood enters at alveolar capillary interface
2. O2 transported in blood dissolved in plasma or bound to haemoglobin
3. oxygen diffuses into cells
4. CO2 diffuses out of cells
5. CO2 is transported, bound to haemoglobin or HCO3- (carbonate)
6. CO2 enters alveoli at alveolar capillary interface

Question 3

what is the importance of haemoglobin?

Answer 3

• facilitates oxygen transport
• takes oxygen from lungs to tissues
• allows oxygen to diffuse

Question 4

the significance of the shape of the haemoglobin-oxygen dissociation curve

Answer 4

• highlights how the pressure of O2 increases, haemoglobin saturation plateaus
• can have normal amounts of O2 carried to cells until decreases past 60mmHg

Question 5

why the Bohr shift is beneficial during exercise

Answer 5

• as pH drops, saturation decreases
• as increased amount of CO2 becomes present during CO2, when diffuses allows pH to increase and O2 saturation to increase also

Question 6

the physiological and chemical factors that influence the haemoglobin-oxygen dissociation curve?

Answer 6

pH, temp, CO2, BPG, CO

Question 7

the relationship between CO2 and pH and the role or carbonic anhydrase?

Answer 7

balances out pH and allows CO2 to be expelled during breathing