(pg S59)
• Katherine wants to investigate if she adds fertilizer before she waters her plants or after watering?
• 1. Will water move into or out of a plant cell if the cell has higher water potential than the surrounding environment?
• 2. What would happen if you applied saltwater to
• the root of a plant?
• 3. If you place fertilizer before you water the grass,
• will that change the movement of water into
• the plant?

• Design an experiment to identify the Molar (M) concentrations of the sucrose solutions and use the solutions to determine the water potential of the plant tissue.
• *Use different potatoes (potatoes, yams, sweet potatoes)
• *Unknown M concentration
• *Different sizes of cubes
– (surface area)

• Procedures:
• 1. Cut four (4) potato cubes (DO NOT include skin).
• 2. Mass your four cubes (1 set) for Initial weight.
• 3. Place cubes in cups with sucrose solution molarity. Label cups
• 4. Make observations and place cups in order of Molarity.
• 5. Let it stand overnight (24hrs)
• 6. Mass your four cubes for Final weight. Calculate % change in mass.
• 7. Construct a Graph with class data

• 1. How can you measure the plant pieces to determine the rate of diffusion?
• 2. How would you calculate the water potential in the cells?
• 3. How can you determine which color of water is which M sucrose concentration?
• 4. Which solution had a water potential equal to that of the plant cells? how do you know?
• 5. What would your results be if the potato were placed in a dry area for several days before your experiment?
• 6. When potatoes are in the ground, do they swell with water when it rains?