Question

a red blood cell placed in a hypertonic medium will
multiple choice
expand
burst.
shrink.
have no change in shape.
become a white blood cell.

Explanation:

In a hypertonic medium, the solute concentration outside the red blood cell is higher than inside. By osmosis, water moves out of the cell to the area of higher solute concentration. This causes the red blood cell to lose water and shrink. Expanding or bursting would happen in a hypotonic medium (lower solute outside, water enters the cell). No shape change is in an isotonic medium. Red blood cells don't become white blood cells.

Answer:

C. shrink (assuming the third option is labeled C; if the options are unlabeled by letter, then "the third option (shrink)")