Beet root if kept in cold water anthocyanin does not come out due to plasma membrane

The correct option is Impermeable to anthocyanins.

Here is the step-by-step explanation of why this is correct:

1. Understanding Anthocyanin:
Anthocyanin is a water-soluble pigment found in the vacuole of beetroot cells. It gives beetroot its characteristic deep red or purple color.

2. Role of the Plasma Membrane:
In a living beetroot cell, the vacuole is surrounded by a membrane (tonoplast), and the cell itself is enclosed by the plasma membrane. Under normal, cold water conditions, these membranes remain intact, functional, and selectively permeable. They act as a physical barrier preventing large polar solute molecules like anthocyanin from passing through.

3. Why the Pigment Does Not Leak in Cold Water:
Because the plasma membrane is impermeable to anthocyanins under normal conditions, the pigment is retained inside the cell. It cannot diffuse out into the surrounding cold water. However, if the beetroot is boiled or treated with chemicals, the membrane proteins denature, and the lipids are disrupted, making the membrane leaky and allowing the pigment to escape.