When blood cells are placed in \(1\%\) (w/v) \(NaCl\) aqueous solution:

Cell will shrink

The correct answer is option 2. Cell will shrink.

When blood cells are placed in \(1\%\) (w/v) \(NaCl\) aqueous solution: Cell will shrink

The reason behind this is as follow:

Tonicity: This refers to the relative concentration of solutes (dissolved particles) between a cell and its surrounding environment. A solution can be:

Isotonic: Same solute concentration as the cell (no net movement of water).

Hypertonic: Higher solute concentration than the cell (water moves out of the cell).

Hypotonic: Lower solute concentration than the cell (water moves into the cell).

Explanation:

Blood cells are surrounded by a semipermeable membrane that allows water to pass through but restricts the movement of most dissolved solutes (like \(NaCl\)).

A 1% \(NaCl\) solution is more concentrated (hypertonic) compared to the internal environment of the blood cell.

Due to the concentration difference, water will tend to move out of the cell (osmosis) to reach equilibrium across the membrane.

This outward movement of water will cause the blood cell to shrink.

Therefore, placing blood cells in a 1% \(NaCl\) solution will lead to their shrinkage.