To reduce brain swelling by pulling water out of brain cells, a substance can be injected intravenouslytoincrease the osmotic pressure of interstitial fluid. Which of the following properties must this substance lack in order to be effective?
A) permeable to capillary endothelium
B) nontoxic to neurons
C) permeable to brain plasma membranes
D) impermeable to brain plasma membranes
E) soluble in water

Question

Quizplus · Accepted Answer

For a substance to effectively reduce brain swelling by pulling water out of brain cells, it must not be permeable to brain plasma membranes. If it were permeable, it would enter the cells and not create the osmotic gradient needed to draw water out of the cells.

To Reduce Brain Swelling by Pulling Water Out of Brain