Bohr Shifts

[stupidcancer93]

Hey Guys,

I was wondering if my logic is right.
The Y axis is oxygen % saturation, and X axis is P O2. And it's a sigmoidal curve.
Saturation=Affinity

So when there's an increase in pCO2, dec H+ There is a shift to the RIGHT because the bodies tissues need more oxygen so Hb needs a lower affinity/saturation for the O2 so it can release it in the body.

When there's a decrease in pCO2 and inc in H+ there is a shift to the LEFT because we don't need to release oxygen as much to the bodies tissues so Hb can still grip it tightly.

What about when there's Carbon Monoxide. Hb likes CO more than O2, so Hb will not release ( lower affinity/ saturation) for O2 as much so there will be a leftward shift?

---

Members don't see this ad.

 

[dudewheresmymd]

Hey Guys,

I was wondering if my logic is right.
The Y axis is oxygen % saturation, and X axis is P O2. And it's a sigmoidal curve.
Saturation=Affinity

So when there's an increase in pCO2, dec H+ There is a shift to the RIGHT because the bodies tissues need more oxygen so Hb needs a lower affinity/saturation for the O2 so it can release it in the body.

When there's a decrease in pCO2 and inc in H+ there is a shift to the LEFT because we don't need to release oxygen as much to the bodies tissues so Hb can still grip it tightly.

What about when there's Carbon Monoxide. Hb likes CO more than O2, so Hb will not release ( lower affinity/ saturation) for O2 as much so there will be a leftward shift?

If there's an increase in pCO2, there is a increase in H+ /decrease in ph oxygen dissociation curve shifts to the right

If there's a decrease in pCO2, there is a decrease in H+/an increase in ph and thus the curve shifts to the left.

Both of these occur because CO2+H2O are converted to H2CO3 (carbonic acid) via carbonic anhydrase which then dissociates into H+ and HCO3-. So think Le chatliers when you do these types of questions.

 

[AFLATPEG]

What about when there's Carbon Monoxide. Hb likes CO more than O2, so Hb will not release ( lower affinity/ saturation) for O2 as much so there will be a leftward shift?

Yes.

CO has an affinity for Hb 200x more than O2. When CO binds to Hb, it causes the O2 on the other sites to bind with greater affinity, thus not releasing the O2. CO causes the curve to move to the left (and downward too).