What does extracellular fluid contain?

What is membrane potential?

A red blood cell's intracellular salt concentration is around 150 mM. The cell is placed in a 500 mM sodium chloride beaker. (a) Explain how osmosis will affect the cell if the cell membrane is permeable to water but not to ions. (b) If the membrane were permeable to ions, which direction would solutes diffuse in: into or out of the cell?

What do diffusion, facilitated diffusion, and osmosis have in common? In what way do they differ?

What are organelles?

How does the cytosol, or intracellular fluid, differ in composition from the extracellular fluid?

In which fluid cells are suspended?