Temperature effects on beetroot cell membranes

Steps:

• Beetroot cubes release red anthocyanin if membranes are damaged, coloring the solution.
• Clear solution indicates intact membranes; red indicates permeability increase.
• Evaluate treatments: acid denatures proteins, ethanol dissolves lipids, room-temperature water has no effect, hot water disrupts structure.
• Match explanations to expected outcomes for each observation.

Why D is correct:

• High temperature fluidizes membrane lipids per the fluid mosaic model, increasing permeability and explaining anthocyanin leakage (red color, though recorded as clear here—assumes rapid damage).

Why the others are wrong:

• A: Acid denatures proteins causing red color, but explanation incomplete without specifying denaturation.
• B: Ethanol dissolves lipids leading to red color, not clear.
• C: Room-temperature water leaves membranes intact (clear), not red.

Final answer: D