In the plasma, the quantity of oxygen in solution is:

• A. higher than the amount bound to hemoglobin
• B. equal to the amount bound to hemoglobin
• C. zero, since oxygen does not dissolve in plasma
• D. relatively low compared to the amount bound to hemoglobin

Answer: (D)

Verified step by step guidance

1. Understand that oxygen in blood exists in two main forms: dissolved in plasma and bound to hemoglobin within red blood cells.
2. Recall that oxygen is only sparingly soluble in plasma, so the amount of oxygen physically dissolved in plasma is relatively low.
3. Recognize that the majority of oxygen in blood is transported bound to hemoglobin, which greatly increases oxygen carrying capacity.
4. Compare the quantities: the oxygen bound to hemoglobin is much higher than the oxygen dissolved in plasma under normal physiological conditions.
5. Conclude that the amount of oxygen dissolved in plasma is relatively low compared to the amount bound to hemoglobin.