What is the role of nitric oxide in regulating hemoglobin's oxygen binding properties?

A Increases oxygen affinity
B Decreases oxygen affinity ✓
C Has no effect on oxygen binding
D Enhances carbon dioxide transport

Explanation

Nitric oxide binds to the heme group of hemoglobin, decreasing its oxygen affinity and facilitating the release of oxygen to tissues.

Source

Scientific literature on nitric oxide and hemoglobin interaction
Hematology Hematology: Hemoglobin and Oxygen Transport Hematology: Hemoglobin and Oxygen Transport Hard MEDICAL Confidence: medium