Osmosis

Open Ended

Why is osmosis important for living organisms?

Fill in the Blanks

Osmosis is the passage of

from a region of higher water potential to a region of lower water potential through a partially permeable membrane.

Multiple Choice

Which of the following statements best describes water potential?

• It is the measure of the potential for water to move out of a solution by osmosis.

• It is the amount of water in a solution.

• It is the temperature at which water boils.

• It is the pressure exerted by water vapor.

Open Ended

Explain how adding solutes to pure water affects its water potential.

Fill in the Blanks

Water molecules are in constant motion and move in and out of a partially permeable membrane. Net movement will be from the area where there are most water molecules. Fill in the blank: Net movement of water will be from the area of ___ water concentration to ___ water concentration.

Multiple Choice

Which of the following statements about osmosis is correct based on the diagram?

• Water moves from the side with more solute to the side with less solute.

• Water moves from the side with less solute to the side with more solute.

• Solute moves through the membrane instead of water.

• There is no net movement of water.

Multiple Select

Select all correct statements about the movement of water in relation to water potential and solution concentration.

• Water moves from a higher (less negative) water potential to a lower (more negative) water potential.

• Water moves from a more concentrated solution to a dilute solution.

• Water moves from a dilute solution to a more concentrated solution.

• Water moves from a lower (more negative) water potential to a higher (less negative) water potential.

Open Ended

Where does water move to among the following water potentials: -1 kPa, -4 kPa, -8 kPa? Explain your reasoning.

Open Ended

What will happen to an animal cell placed in distilled water? Explain in terms of water potential.

Multiple Choice

Which process is depicted in the sequence of images showing the breakdown of red blood cells, and what is the result called?

• Plasmolysis, resulting in cell shrinkage

• Haemolysis, resulting in cell bursting

• Crenation, resulting in spiky cells

• Turgidity, resulting in swollen cells

Open Ended

What is happening to red blood cells when placed in a salt solution?

Multiple Choice

Which of the following statements about osmosis in plant cells are correct?

• A cell wall is partially permeable.

• A cell membrane is fully permeable.

• A cell is turgid when the osmotic force moving water in is balanced by the pressure potential.

• The cytoplasm of a plant cell shrinks when it takes in water.

Fill in the Blanks

Osmotic potential is a measure of the potential of a solution to cause water to move into a cell across a

membrane as a result of dissolved solutes.

Fill in the Blanks

Water potential is the sum of

pressure and osmotic potential.

Open Ended

What has happened to the plant cells in water? Why?

Open Ended

What has happened to the plant cells in salt solution? Why?

Fill in the Blanks

Incipient plasmolysis occurs when the cell membrane pulls away from the

.

Multiple Select

Which of the following statements about osmotic concentrations is/are correct?

• In an isotonic solution, the osmotic concentration of solutes is the same as inside the cell.

• In a hypotonic solution, the osmotic concentration of solutes is higher than in the cell.

• In a hypertonic solution, the osmotic concentration of solutes is lower than in the cell.

• In a hypertonic solution, the osmotic concentration of solutes is higher than in the cell.

Open Ended

How would you explain the importance of a partially permeable membrane in the process of osmosis?

Multiple Choice

What is the main factor that drives the movement of water during osmosis?

• Difference in water potential

• Presence of solute

• Temperature gradient

• Pressure difference