Haemoglobin Flashcards
Why does haemoglobin have a quarternary structure
4 polypeptide chains
What is a haem group
Iron
What affinity for oxygen does haemoglobin have
High
What is oxygen partial pressure
Oxygen concentration
The amount of pressure oxygen atoms exert in a total volume of gas
When does haemoglobin load oxygen
High oxygen partial pressure
When does haemoglobin unload oxygen
Low partial pressure of oxygen
Eg. High CO2 partial p
Give an example of when haemoglobin has a high affinity for oxygen
Lungs
Give an example of when haemoglobin has a low affinity for oxygen
Repairing muscle cells
What shape is the oxygen dissociation curve
Sigmoid
Why is the oxygen dissociation curve a sigmoid shape
1 = hard = polypeptide chains bound tightly. Binding sights are no exposed 2/3 = easy = bases are exposed 4 = hard = due to probability it is unlikely it will bind
Explain why there is low saturation at low partial p
Haemoglobin has a low affinity for oxygen
Oxygen readily unloads
Eg. Muscle cells
Explain why there is a high saturation at high partial p
Haemoglobin has a high affinity for oxygen
Readily loads oxygen
Eg. Alveoli
Explain the Bohr effect
Respiring cells have high partial p of CO2
Shifts position of curve to the right
At a higher p(O2) the saturation is lower
Oxygen more readily unloads (has a lower affinity)
What position does the curve shift in high p(CO2)
Right
Which way does the curve shift in high p(O2)
Left
Which way do animals who live in low levels on O2 curve shift and why
Left
Need haemoglobin with a higher affinity for oxygen in lower pp
So at a lower pp the saturation is higher
Which way do very active animals curve shut and why
Right
High oxygen demand at respiring cells
Need haemoglobin with lower affinity for O2
So at a high pp the saturation is lower
