# Worksheet: Osmosis

In this worksheet, we will practice describing the process of osmosis and explaining how we can investigate the effect of osmosis in plant tissues.

Q1:

A student reads, “A root hair cell has a higher concentration of mineral ions than the surrounding soil.” He concludes that water will move out of the root hair cell and into the soil. Is the student correct or incorrect?

• ACorrect
• BIncorrect

Q2:

Fill in the blanks:

If a solution has a large amount of sugar dissolved in it, it has a solute concentration.

• Alow
• Bhigh

If a solution has a low solute concentration, it has water potential.

• Alow
• Bhigh

Water will move from water potential to water potential.

• Alow, high
• Bhigh, low

Q3:

A student takes two spoonfuls of sugar and stirs them in warm water until all the sugar is dissolved.

In this scenario, what is the solute?

• ASugar
• BNeither
• CSugar and water
• DWater

In this scenario, what is the solvent?

• ASugar and water
• BNeither
• CSugar
• DWater

Q4:

Osmosis moves water down a concentration gradient. Which of the following best describes a concentration gradient?

• AThe concentration of two areas
• BThe difference between two concentrations
• CThe difference between an acidic and an alkaline substance
• DThe dissolving of a large amount of solute in a small amount of solution
• EThe movement of concentration

Q5:

After a practical exam, a student wanted to calculate the percentage change in mass of two apples.

The starting mass of apple A was 5.07 g and its final mass was 3.23 g. Calculate its percentage change to two significant figures.

• A
• B
• C
• D
• E

The starting mass of apple B was 4.89 g and its final mass was 7.20 g. Calculate its percentage change to two significant figures.

• A
• B
• C
• D
• E

Q6:

A partially permeable bag is placed in a solution that is hypertonic to it. Which of the following correctly describes what will happen to the bag?

• AThe bag will decrease in mass as the water moves out of it.
• BThe bag will increase in mass as water moves into it.
• CThe bag will increase in mass as the solutes move into it.
• DThe bag will decrease in mass as the solutes move out of it.
• EThere will be no change to the mass of the bag.

Q7:

A student wanted to investigate osmosis in plant tissue. They took two slices of apple and recorded their starting mass. They placed one slice into test tube A, containing 90% sucrose solution, and the other slice into test tube B, containing 10% sucrose solution. They then left the experiment for 20 minutes before removing the apple slices and recording their final mass.

In the practical described, which of the following is an example of a control variable?

• ATime
• BStarting mass of apple
• CChange in mass
• DDifferent concentrations of sucrose

Which of the following is the dependent variable?

• BTime
• CNone of the other choices is correct.
• DChange in mass

Which of the following is the independent variable?

• BChange in mass
• CTime
• DType of apple

In which tube would the piece of apple lose the most mass?

• ATube B
• BTube A

Q8:

A red blood cell is placed into a solution with a low solute concentration. What will happen to the red blood cell and why? Choose the most accurate answer.

• AThe water in the solution will move into the red blood cell and cause the red blood cell to increase in size because the blood cell has a lower water potential than the solution.
• BThere will be no overall change to the red blood cell.
• CThe water in the red blood cell will move into the surrounding solution and the cell will shrink because the blood cell has a lower water potential than the solution.
• DThe water in the solution will move into the red blood cell and cause the red blood cell to increase in size because the blood cell has a higher water potential than the solution.

Q9:

A potato chip is placed into a highly salty solution. What is the best description for what would happen to this potato chip?

• AThe mass of the potato chip would stay the same.
• BThe potato chip would gain mass because the solutes would move from the solution into the potato.
• CThe potato chip would lose mass because the solutes would move from the potato into the solution.
• DThe potato chip would lose mass because the water would move from the cells in the potato chip into the salty solution.
• EThe potato chip would gain mass because water would move from the solution and into the cells of the potato chip.

Q10:

Fill in the blanks.

If a solution is , it has the same concentration of solutes as the cell it is surrounding.

• Aisotonic
• Bhypertonic
• Chypotonic

If a solution is , it has a higher concentration of solutes than the cell it is surrounding.

• Aisotonic
• Bhypertonic
• Chypotonic

If a solution is , it has a lower concentration of solutes than the cell it is surrounding.

• Aisotonic
• Bhypertonic
• Chypotonic

Q11:

Which of the following correctly defines osmosis?

• AThe movement of gas molecules from high to low concentrations
• BThe movement of particles from an area of high solute concentration to an area of low solute concentration through a selective membrane
• CThe movement of solute particles
• DThe movement of water particles from an area of low solute concentration to an area of high solute concentration through a partially permeable membrane
• EThe movement of water particles from an area of low concentration to an area of high concentration