3.4 haemoglobin, transport of oxygen

what is affinity of haemoglobin for oxygen

the ability of haemoglobin to attract or bind to oxygen

what is saturation of haemoglobin with oxygen

when haemoglobin is holding the maximum amount of oxygen it can bind to (4)

what is loading/association of haemoglobin

the binding of oxygen to haemoglobin

what is partial pressure

measure of how much O₂ compared to other gasses

explain oxyhaemoglobin dissociation curve

oxygen is loaded in regions with a high partial pressure of oxygen i.e. alveoli)

unloaded in regions of low partial pressure of oxygen (respiring tissues)

what is the Bohr effect

when a high carbon dioxide concentration causes the oxyhaemoglobin curve to shift to the right

affinity for oxygen decreases because the acidic carbon dioxide changes the shape of haemoglobin slightly

explain haemoglobin molecule

• 4 polypeptide chains (quaternary)

• each polypeptide chain has a prosthetic haem group

what is haem group

-iron ion (Fe²⁺)

-diatomic (has to be 2 of them i.e. O₂)

-associate with 1 molecule of O₂

what do higher and lower affinity of haemoglobin mean

• higher - associates with oxygen easily but releases oxygen less readily

• lower - associates with oxygen less easily but releases oxygen more readily

equation to form oxyhaemoglobin

Hb. + 4O₂ ^>_< Hb(O₂)₄