Question

A cell will swell up if

• A. The concentration of water molecules in the cell is higher than the concentration of water molecules in the surrounding medium
• B. The concentration of water molecules in surrounding medium is higher than water molecules concentration in the cell
• C. The concentration of water molecules is same in the cell and in the surrounding medium
• D. Concentration of water molecules does not matter

Answer 1

The correct option is B

The concentration of water molecules in surrounding medium is higher than water molecules concentration in the cell

The correct option is B.

Explanation of the correct option:

1. The cell swells up when endosmosis occurs.
2. Endosmosis is when the water molecules move from the outside to the inside of the cell through the cell membrane.
3. For example, the passage of water from root hair cells to cortical cells of the root.
4. Water molecules move along the concentration gradient, that is, from higher concentration to lower concentration.
5. So, for a cell to swell, it has to be placed in a hypotonic solution.

Explanation of the incorrect options:

Option A:

If the concentration of water molecules in the cell is higher than the concentration of water molecules in surrounding medium, the cell will lose water.

Option C:

If the concentration of water molecules is the same in the cell and in the surrounding medium, there will be no change in the cell.

Final answer: A cell will swell up if the concentration of water molecules in the surrounding medium is higher than water molecules concentration in the cell.