Haemoglobin Flashcards
(27 cards)
What carries oxygen in red blood cells?
Haemoglobin.
What is the role of iron ions in red blood cells?
Associate with oxygen.
Why can iron ions bind to oxygen?
They are charged/polar and part of haemoglobin.
What forms when oxygen binds to haemoglobin?
Oxyhaemoglobin.
Where does haemoglobin load oxygen?
In the lungs.
Why does haemoglobin load oxygen in the lungs?
High partial pressure of oxygen.
How saturated is haemoglobin in the lungs?
Almost 95% / 100% saturated.
Where does haemoglobin unload oxygen?
In tissue cells.
Why does haemoglobin unload oxygen in tissues?
Low partial pressure of oxygen.
What increases oxygen unloading in tissues?
Increased carbon dioxide.
What causes the oxygen dissociation curve to shift right?
Presence of carbon dioxide.
What is the benefit of the curve shifting right?
More oxygen is unloaded.
What other conditions increase oxygen unloading?
Increased temperature or acidity.
Where do low pO2, high CO2, and high temp occur?
Near respiring tissues.
What happens when the first O2 binds to haemoglobin?
It changes haemoglobin’s structure.
What does this structural change do?
Makes it easier for the next oxygen to bind.
How many O2 molecules can haemoglobin carry?
Four.
Where is haemoglobin found?
In red blood cells.
What happens when respiration increases?
CO2 increases.
What happens when CO2 increases?
More oxygen dissociates from haemoglobin.
What is dissociated when CO2 increases?
Oxygen from haemoglobin.
How does oxygen reach respiring tissues?
It diffuses from red blood cells to tissues.
What happens to blood pH when CO2 increases?
pH decreases / acidity increases.
How does low pH affect haemoglobin’s affinity for O2?
Decreases its affinity.
