NCLEX RN Questions on Respiratory System Related

Review NCLEX RN Questions on Respiratory System related questions and content

Double Bohr effect (Oxygen curves for maternal and foetal Hb move apart in opposite directions) occurs in

  • A. Foetal circulation
  • B. Maternal circulation
  • C. In the Placenta operating in both maternal and foetal circulations
  • D. In the uterine wall
Correct Answer: C

Rationale: Rationale:
1. In the placenta, maternal and fetal blood circulations are in close proximity.
2. Maternal Hb releases oxygen to fetal Hb due to the lower affinity of fetal Hb for oxygen.
3. This double Bohr effect causes the oxygen dissociation curves of maternal and fetal Hb to move apart.
4. This occurs specifically in the placenta where both maternal and fetal circulations operate.

Summary:
A. Incorrect. Double Bohr effect doesn't occur solely in fetal circulation.
B. Incorrect. Double Bohr effect doesn't occur solely in maternal circulation.
C. Correct. Placenta facilitates the exchange between maternal and fetal blood causing the double Bohr effect.
D. Incorrect. Double Bohr effect is not related to the uterine wall.