Haemoglobin Flashcards
What structure do haemoglobin have?
Quaternary
What is a Quaternary structure
More than one (four) polypeptide chains bonded together
What does Haemoglobin contain?
Hem group
what do haem molecules do?
oxygen binds to it, reversibly
What is Haemoglobin responsible for?
carrying oxygen from the gas exchange to cells for respiration
level of oxygenation
air pressure X proportion of oxygen in air
once an oxygen molecule binds what happens?
the quaternary structure changes to allow rapid binding of oxygen to the haem groups (high affinity for oxygen)
Once one oxygen molecule leaves the haemoglobin molecule what happens?
The quaternary structure changes to allow rapid release of oxygen to the surrounding respiring cells. (low affinity for oxygen)
How have different organisms adapted to live in different environments?
oxygen dissociation curves to left or right
if to the left then oxygen can bind more easily (low oxygen environment)
if to th right then oxygen binds less readily allowing oxygen to be easily released in the cells
where to foetuses have their oxygen dissociation curves?
to the left
allows them to absorb oxygen from mothers blood
how does the carbon dioxide level in the blood effect haemoglobin?
Carbon dioxide absorbed into red blood cells
decrease the PH of blood
which in turn decreases the affinity for oxygen
this means that as red blood cells receive carbon dioxide from cells they give off oxygen