Final answer:
The shrinking of the cytoplasm of a plant cell when placed in a hypertonic solution is called plasmolysis.
Step-by-step explanation:
The shrinking of the cytoplasm of a plant cell when placed in a hypertonic solution is called plasmolysis. Plasmolysis occurs when water moves out of the cell through osmosis, causing the cytoplasm to shrink and the cell membrane to pull away from the cell wall. This is a defense mechanism for the plant cell to prevent excessive water loss.
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