hi
i agree it’s tricky, are you sure it’s not B)?
if you look at the graph, 1) must be wrong, we need a higher partial pressure of oxygen so we shift to the right
option 3) must be wrong, a shift to the right means the Bohr effect increases
option 2) is correct, 2,3BPG competes with O2 to bind with haemoglobin so it reduces Hb affinity for O2
option 4) should be correct, if you draw a vertical line on the graph, the normal curve has a higher SO2 than the right shift for a same value of x
for option 4) to be false, maybe they mean that Hb is now MORE likely to unload O2 in TISSUES?
Bohr Affect Question & Partial Pressures
- Shift Left = High affinity & LOWER Partial Pressure (FALSE)
- Binding require Increase Partial Pressure 50% = Lower affinity (TRUE)
- ??? We know 2/4 are good so it leaves us only one option
- When absent Oxyheme has higher affinity = less unloading (TRUE)
Option B Correct
probably that’s what they meant it was a bit of a more complicated one but its always good to think about it in a different why