Plasmolysis creates a space filled with external solution

Steps:

• Plasmolysis occurs when a plant cell loses water in a hypertonic solution, causing the plasma membrane to pull away from the cell wall.
• In partial plasmolysis, the protoplast shrinks but remains attached at some points, forming a gap labeled Z.
• This gap between the cell wall and plasma membrane fills with the surrounding hypertonic solution.
• Z must contain the external solution, identified as Y in the diagram setup.

Why C is correct:

• By definition, the plasmolysis space is occupied by the external hypertonic solution (Y), as water exits the cell but the solution enters the gap.

Why the others are wrong:

• A: Air cannot enter the sealed cell wall space; it's a liquid-filled gap.
• B: Solution X is likely the internal cell solution, not the external one in the gap.
• D: Water would prevent plasmolysis by maintaining turgor; the gap forms due to its loss.

Final answer: C