Final answer:
The idea that approximately 0.3 mL of oxygen is free-floating per 100 mL of whole blood is false because only about 1.5% of oxygen is dissolved in the blood, while the majority is bound to hemoglobin in red blood cells.
Step-by-step explanation:
The statement that approximately 0.3 mL of oxygen is free-floating per 100 mL of whole blood is False. The majority of oxygen in the blood is bound to hemoglobin, not free-floating.
Oxygen's solubility in blood is relatively low due to the low Henry's law constant for O₂ in water. While some oxygen does dissolve in the blood, it accounts for only about 1.5% of oxygen transport. The rest, approximately 98.5%, is bound to hemoglobin within red blood cells, which can carry four O₂ molecules each. Hemoglobin's role is crucial because it increases the total dissolved O₂ concentration to levels that can support the energy needs of multicellular organisms. Without hemoglobin, the dissolved oxygen level would be nearly a thousand times less. Furthermore, synthetic oxygen carriers have been developed to mimic this function in blood substitutes, achieving comparable oxygen dissolution despite oxygen's low solubility in water.