Final answer:
False. The functionally important differences between blood plasma and interstitial fluid extend beyond the presence of more protein anions in plasma.
Step-by-step explanation:
False. The presence of more protein anions in blood plasma is not the only functionally important difference between blood plasma and interstitial fluid. While it is true that blood plasma contains a higher concentration of protein compared to interstitial fluid, there are other differences as well.
Blood plasma also contains various electrolytes, gases, organic nutrients, metabolic wastes, and other substances, such as hormones and antibodies. Interstitial fluid, on the other hand, contains a different composition of solutes depending on the exchanges between the cells in the tissue and the blood. It lacks red blood cells, platelets, and plasma proteins, but may contain some types of white blood cells.