Flashcards in 8.4 Transport Of Oxygen And Co2 In The Blood Deck (12)
Loading flashcards...
1
What is haemoglobin
Red pigment that carries oxygen in the blood
Very large globular conjugated protein made up of 4 peptide chains
They can bind to 4 oxygen molecules
2
What is positive cooperativity if heamoglobin
The arrangement of haemoglobin means that as soon as one oxygen molecule binds to the haem group the molecule will change shape making it easier for the next oxygen molecule to bind
3
What do oxygen dissociation curves show
The affinity of haemoglobin for oxygen
4
Why does the curve on the oxygen dissociation level out
The haemoglobin becomes fully saturated at very high partial pressure of oxygen because all the haem groups are bound to oxygen
5
What is the effect of co2 on haemoglobin affinity
What effect does it cause
The higher the partial pressure of co2 the more easily the haemoglobin gives up oxygen
Causes the Bohr effect
6
What is the importance of the Bohr effect
In active tissues with a High pp of co2 haemoglobin gives up 02 easier
In lungs where the pp of co2 is low, oxygen binds to haemoglobin easier
7
How do fetus get oxygen
Fetal haemoglobin has a bigger affinity of oxygen than adult haemoglobin
Therefore it removes oxygen from the maternal blood as they move past each other in the placenta
8
How is co2 transpired from the tissue to the lungs
5% is carried dissolved in the plasma
10-20% is combined with amino groups in polypeptide chains of haemoglobin
Forming carbaminohaemoglobin
75-85% is converted into carbonate ions in the cytoplasm of red blood cells
9
How does carbon dixode turn to hydrogen carbonate ions
Co2 reacts slowly with water to form carbonic acid
This carbonic acid dissocties to form hydrogen ions and hydrogen carbonate ions
10
What enzymes are there in the red blood cells that catalyse the reaction between co2 and water to from
Carbonic acid
Carbonic anhydrase
11
What is the chloride shift
Negatively charged hydrogen carbonate ions move out is the cell red blood cells into the plasma by diffusion
The negatively charged chloride ions move into the red blood cells which maintains the electrical balance of the cell
12
