Question

a cell is dropped into a saltwater solution and shrivels up. you infer that, compared to the cell, the type of saltwater solution is (1 point)
○ isotonic.
○ hypotonic.
○ tonic.
○ hypertonic.

Explanation:

To solve this, we recall the concepts of tonicity:

• An isotonic solution has the same solute concentration as the cell, so no net water movement occurs, and the cell doesn't shrivel.
• A hypotonic solution has a lower solute concentration than the cell, so water enters the cell, causing it to swell (not shrivel).
• The term "tonic" is not a specific tonicity term for this context.
• A hypertonic solution has a higher solute concentration than the cell. In this case, water moves out of the cell (to the area of higher solute concentration, the saltwater solution) via osmosis, causing the cell to shrivel.

Since the cell shrivels, the saltwater solution must have a higher solute concentration than the cell, meaning it is hypertonic.

Answer:

D. hypertonic.