Question

below are animal cells placed in beakers of various concentrations.

1. draw an arrow to show which way the water would move by osmosis
2. fill in any missing percentages (water or solute)
3. identify the type of solution (isotonic, hypertonic, or hypotonic)

Explanation:

Step1: Recall osmosis principles

Osmosis is the movement of water from an area of high - water concentration to an area of low - water concentration across a semi - permeable membrane. An isotonic solution has equal water and solute concentrations inside and outside the cell, a hypertonic solution has a higher solute concentration outside the cell (lower water concentration), and a hypotonic solution has a lower solute concentration outside the cell (higher water concentration).

Step2: Analyze first cell - beaker pair

The cell has 90% H₂O and 10% solute, and the beaker has 85% H₂O and 15% solute. Water moves from the cell (higher water concentration) to the beaker (lower water concentration). The solution is hypertonic.

Step3: Analyze second cell - beaker pair

The cell has 40% H₂O and 60% solute, and the beaker has 90% H₂O and 10% solute. Water moves from the beaker (higher water concentration) to the cell (lower water concentration). The solution is hypotonic.

Step4: Analyze third cell - beaker pair

The cell has 75% H₂O and 25% solute, and the beaker has 80% H₂O and 20% solute. Water moves from the beaker (higher water concentration) to the cell (lower water concentration). The solution is hypotonic.

Step5: Analyze fourth cell - beaker pair

The cell has 45% H₂O and 55% solute, and the beaker has 75% H₂O and 25% solute. Water moves from the beaker (higher water concentration) to the cell (lower water concentration). The solution is hypotonic.

Step6: Analyze fifth cell - beaker pair

The cell has 90% H₂O and 10% solute, and the beaker has 63% H₂O and 37% solute. Water moves from the cell (higher water concentration) to the beaker (lower water concentration). The solution is hypertonic.

Step7: Analyze sixth cell - beaker pair

The cell has 50% H₂O and 50% solute, and the beaker has 50% H₂O and 50% solute. There is no net movement of water. The solution is isotonic.

Step8: Analyze seventh cell - beaker pair

The cell has 90% H₂O and 10% solute, and the beaker has 90% H₂O and 10% solute. There is no net movement of water. The solution is isotonic.

Step9: Analyze eighth cell - beaker pair

The cell has 82% H₂O and 18% solute, and the beaker has 25% H₂O and 75% solute. Water moves from the cell (higher water concentration) to the beaker (lower water concentration). The solution is hypertonic.

Step10: Analyze ninth cell - beaker pair

The cell has 90% H₂O and 10% solute, and the beaker has 80% H₂O and 20% solute. Water moves from the cell (higher water concentration) to the beaker (lower water concentration). The solution is hypertonic.

Answer:

For the first pair: Water moves from cell to beaker, hypertonic.
For the second pair: Water moves from beaker to cell, hypotonic.
For the third pair: Water moves from beaker to cell, hypotonic.
For the fourth pair: Water moves from beaker to cell, hypotonic.
For the fifth pair: Water moves from cell to beaker, hypertonic.
For the sixth pair: No net water movement, isotonic.
For the seventh pair: No net water movement, isotonic.
For the eighth pair: Water moves from cell to beaker, hypertonic.
For the ninth pair: Water moves from cell to beaker, hypertonic.