D2.3.2 Water movement from less concentrated to more concentrated solutions

What is the difference between solute and solvent?

Solute: A substance that is dissolved in a solution; Solvent: The liquid in which the solute is dissolved.

Define solute concentration.

The amount of solute present in a given quantity of solvent or solution.

What drives the movement of water molecules?

Differences in solute concentration.

What is osmosis?

The net movement of water molecules across a semi-permeable membrane from a region of lower solute concentration to a region of higher solute concentration.

What is a semi-permeable membrane?

A membrane that allows water to pass through but restricts larger solute molecules or ions.

What are the two reasons water moves toward a higher solute concentration?

Intermolecular attractions: Water forms hydrogen bonds with solute, creating a pull; Net movement: More water moves toward the higher solute concentration.

What does it mean for two solutions to be isotonic?

Two solutions with equal solute concentrations, resulting in no net movement of water.

Define hypotonic.

A solution with a lower solute concentration compared to another solution.

Define hypertonic.

A solution with a higher solute concentration compared to another solution.

Why should osmosis be described in terms of solute concentration?

Because osmosis refers to the movement of water from areas of lower solute concentration to higher solute concentration.

What role do hydrogen bonds play in osmosis?

Hydrogen bonds between water and solute molecules create a 'pull' that draws water toward the solute.

Is the movement of water in osmosis one-directional or two-directional?

Water moves in both directions, but there is a net movement toward the higher solute concentration.

What happens to water movement in isotonic solutions?

There is no net movement of water, as the solute concentrations are equal.

Give an example of a hypotonic solution.

A solution with 1% salt compared to a 5% salt solution.

Give an example of a hypertonic solution.

A solution with 10% salt compared to a 5% salt solution.

What is the effect of a hypertonic solution on a cell?

Water moves out of the cell, causing it to shrink or crenate.

What is the effect of a hypotonic solution on a cell?

Water moves into the cell, causing it to swell or burst.

What is the key difference between diffusion and osmosis?

Diffusion is the movement of solute particles, while osmosis is the movement of water molecules.