Gas Exchange System

Question 1

Non infectious disease that affects gas exchange system

Answer 1

-Lung cancer
-Emphysema

Question 2

Describe the role of carbonic anyhrdrase in the transport of carbon dioxide

Answer 2

-Carbonic anyhrdase catalyses the reaction between water and carbon dioxide in the reed blood cells
-This forms carbonic acid which dissociates to form HCO3- & H+
-HCO3- diffuses into the palms a
-It maintains the concentration gradient for the diffusion of carbon dioxide into the RBC
-It removes large amounts of carbon dioxide
( carbonic anhydrase is converted back into CO2 to be exhaled in lungs)

Question 3

How does the structure of hemoglobin molecule make it able to transport oxygen efficiently

Answer 3

• 4 haem present per each hemoglobin
• haem group contains iron atom
• each iron binds to 1 oxygen molecule

Question 4

Explain the advantage of illamas having an oxygen dissociation curve positioned to the left of the curve for humans

Answer 4

• lower partial pressure of oxygen at high altitudes
• at the same partial pressure the % saturation is higher for humans
• haemoglobin has a high affinity to oxygen
• hence sufficient oxygen is deliver to satisfy demand

Question 5

How oxygen enters teh blood stream from an alveolus

Answer 5

Via diffusion
High concentration to low down the diffusion gradient, passively
Through the squamous epithelial layer