HAEMOGLOBIN Flashcards
Where is haemoglobin found
in red blood cells
`What is haemoglobin
protein molecules with a tertiary structure
Explain the structure formation of haemoglobin
1) primary structure - sequence of amino acids in the 4 polypeptide chains
2) secondary structure - each polypeptide chain is coiled into a helix
3) tertiary structure - each polypeptide chain folded into a precise shape
4) quaternary structure - all 4 polypeptides are linked together to form an almost spherical strcuture
Describe the quaternary structure of haemoglobin
each polypeptide is associated with a haem group that contains an Fe2+ ion
Explain how its quaternary structure allows it to carry oxygen and how many
each Fe2+ ion can combine with a single 02 molecule, meaning it can carry 4 in total
What do some haemoglobins have
a high/low affinity got oxygen
Where does oxygen join to the haemoglobin and what does this form
in the lungs , forms oxyhaemoglobin
What is the process of haemoglobin binding with oxygen
loading or associating
What is the process of haemoglobin releasing oxygen
unloading or dissociating
What does a high affinaty of oxygen mean (& low)
takes up oxygen more readily than it releases it (opposite)
What does haemoglobin do to be efficient at transporting oxygen and how does it meet these
1) readily associate with oxygen at the gas exchange surface
2) readily dissociate from oxygen at those requiring it
changes its affinity for oxygen
How does haemoglobin change its affinity for oxygen
under different conditions, when C02 is present it changes shape so binds more loosely to oxygen, so releases it more readily
What is the affinity for oxygen at gas exchange surface and why
high, as high 02 and low C02
What is the affinity for oxygen at respiring tissues and why
low, low 02 and high C02
What is the chemical formula of oxyhaemoglobin
Hb08
