An unripe mango placed in a concentrated salt solution to prepare pickles shrivels because:

It loses water due to osmosis

The correct answer is Option (4) → It loses water due to osmosis

Osmosis is a specific type of diffusion that refers to the movement of water molecules through a semipermeable membrane. This membrane allows the passage of water but restricts the movement of solutes (like salt). Osmosis aims to equalize the solute concentration on both sides of the membrane.

Concentration Gradient: Water moves from an area of lower solute concentration (hypotonic solution) to an area of higher solute concentration (hypertonic solution).

Equilibrium: The goal is to achieve equilibrium, where the concentration of solute is equal on both sides of the membrane.

Scenario: Unripe Mango in Concentrated Salt Solution

Initial Conditions

The unripe mango has a relatively low concentration of solutes (e.g., sugars, organic acids) in its cells compared to the concentrated salt solution outside. The salt solution is hypertonic relative to the mango's internal environment.

Process of Osmosis

When the mango is placed in the concentrated salt solution, water molecules inside the mango's cells begin to move out into the surrounding solution. This movement occurs because the water seeks to balance the concentration of solutes on both sides of the semipermeable membranes (the cell membranes of the mango).

Effects on the Mango

As water exits the cells, the internal water content of the mango decreases.

This loss of water leads to a decrease in turgor pressure (the pressure of the cell contents against the cell wall).

Consequently, the cells become less rigid and the mango starts to shrivel.

Outcome

The physical appearance of the mango changes as it loses water; it becomes wrinkled and shriveled.

This process is commonly used in food preservation, such as making pickles, because the high salt concentration inhibits the growth of bacteria and molds.

Summary

In this scenario, the unripe mango shrivels due to the loss of water through osmosis. The concentrated salt solution creates a hypertonic environment, causing water to move out of the mango’s cells, leading to shriveling. This phenomenon underscores the principles of osmosis and how it affects plant tissues in different solute environments.

Thus, the correct answer remains: It loses water due to osmosis.