gas exchange Flashcards
Where does gaseous exchange occur
Between alveoli and capillaries
What’s the level of Nitrogen measurable in dry air/alveolar air
79% Dry air
75% Alveolar air
What’s the level of Oxygen i’m dry air/alveolar air
21% Dry air
14% Alveolar air
What’s the level of carbon dioxide in dry air/alveolar air
- 04% Dry air
5. 3% alveolar air
What is the level of water vapour in Dry air/alveolar air
0 Dry air
6.2% alveolar air
What are the 2 types of cells lining the alveoli
Numocytes
Type 1 help with gas exchange
Type 2 store and secrete surfactant
What is haemoglobin made of
4 Globins (polypeptide chains)
4 Haem molecules
carry’s 98% of oxygen
Which is more soluble in water, oxygen or carbon dioxide?
Carbon dioxide
When is haemoglobin’s affinity with oxygen highest
After 1 haem molecules has bound with 1 oxygen molecule this changes the overall shape increasing its affinity with oxygen
What is the % of saturation when the partial pressure of oxygen is 80mmHg?
95.8%
What are the forms of transport of carbon dioxide
70% HCO3 Bicarbonate ions
23% haemoglobin
7% dissolved in plasma
How is carbon dioxide bonded with haemoglobin
CO2HB Carbino haemoglobin
Binds with the globin aspect
How is 70% carbon dioxide absorbed
Carbon dioxide binds with water to form carbonic acid. This process is assisted by the enzyme carbonic anhydrase.
This splits into hydrogen ions and bicarbonate ions which then leave the red blood cell body.
How is the ionic composition of the red blood cell maintained during absorption of carbon dioxide
Chloride shift - chloride ions with negative charge diffuse into the cell body
What happens when there is a right shift of the oxygen disassociation curve?
Reduced affinity with oxygen less oxygen is absorbed. This could be due to increased temperature, increased hydrogen ions ( if the level of carbon dioxide increases in blood cell)
This could be due to exercise
