What is a characteristic of Hemoglobin in its relaxed (R) state compared to its tense (T) state?

In its relaxed (R) state, hemoglobin exhibits a higher affinity for oxygen compared to its tense (T) state. This characteristic is crucial for the function of hemoglobin in oxygen transport. The R state allows hemoglobin to bind oxygen more readily in the lungs, where oxygen concentration is high, promoting efficient uptake.

This increased affinity is due to the conformational changes that occur when hemoglobin transitions from the T state to the R state. In the R state, the structure of hemoglobin stabilizes the binding of oxygen to the heme groups, making it easier for oxygen molecules to attach. As a result, hemoglobin can effectively deliver oxygen to tissues that need it, where the concentration of oxygen is lower.

The other options do not accurately reflect the behavior of hemoglobin in its R state. For instance, the T state has a lower affinity for oxygen, which enables hemoglobin to release oxygen more readily in tissues. Consequently, the distinction between these two states—R and T—is fundamental for understanding hemoglobin's role in oxygen transport and delivery throughout the body.