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## Health and medicine

### Course: Health and medicine>Unit 2

Lesson 11: Fetal circulation

# Double Bohr effect

Learn how there are two distinct Bohr effects happening at the same time in the placenta. Rishi is a pediatric infectious disease physician and works at Khan Academy. Created by Rishi Desai.

## Want to join the conversation?

• At , Rishi says that the amount of hemoglobin bound to oxygen is 98%. Did he mean only 98% of hemoglobin was bound to oxygen or 98% of the oxygen molecules are bound to hemoglobin?
• This refers to the % of hemoglobin that is bound by oxygen.
• starting at , Rishi begins talking about the amount of oxygen lost by the mother roughly being equal to the amount gained by the baby. With the yellow lines he shows that the oxygen content in the uterine artery minus the oxygen content in the uterine vein is the amount of oxygen transferred from the mother to the baby, but the white dots on the four lines (and their corresponding partial pressure of oxygen values) as well as the yellow lines he draws connecting these white dots seem randomly chosen- what do these represent? Why are the baby's two white dots simply in the middle of their respective lines while the mother's two dots appear in the middle and at the maxima, respectively?
• the white dots are chosen based off of known values of pO2 (the x-axis in this case)!
• Bit of a side question, but why is oxygen measured in mercury units?