How does water loss affect cellular hydration?

How does water loss affect cellular hydration?

• A. Cells become dehydrated and shrunken as water moves into the plasma
• B. Cells swell as water leaves the plasma
• C. No change to cellular size
• D. Cells split due to osmotic pressure

Answer: (A)

Osmosis and tonicity determine how water moves between the cell and its surroundings. When the extracellular fluid (the plasma) is more concentrated than the inside of the cell, water moves out of the cell into the plasma. The cell loses water, its volume shrinks, and it becomes dehydrated. This is exactly what happens when water exits the cell to enter the plasma. If water moved into the cell instead (a hypotonic situation), the cell would swell, not shrink. Extremely high water influx can cause lysis, but that is not the described situation here.

Osmosis and tonicity determine how water moves between the cell and its surroundings. When the extracellular fluid (the plasma) is more concentrated than the inside of the cell, water moves out of the cell into the plasma. The cell loses water, its volume shrinks, and it becomes dehydrated. This is exactly what happens when water exits the cell to enter the plasma. If water moved into the cell instead (a hypotonic situation), the cell would swell, not shrink. Extremely high water influx can cause lysis, but that is not the described situation here.