What happened to the iodine, the starch, the glucose and the water in your experiment? Explain which molecules did/did not cross the membrane and in which direction they moved. Substance Prediction Results Starch Starch will stay in the cellulose tubing The results were correct Glucose Glucose will defuse and move out The results were correct Iodine The iodine will change color The results were correct 2. Did the results of your experiment agree or disagree with your prediction?
Why or why not? My results agreed with my prediction because the starch, glucose and iodine stayed in the cellulose tubing, or the water changed color. 3. Considering your observations, suggest an explanation for the results of your experiment. What assumptions did you make about the nature of the membrane? The cell contains what enters. Small molecules can quickly go through and out of the cell. Meaning the small molecule diffuse through the process of osmosis. Lab 2 – ELODEA
Objective: To demonstrate and explain effects of osmosis across a living membrane. 1. What changes took place in the Elodea cell after salt water is added? Did these changes agree or disagree with your prediction? Why or why or not? When the salt was added to the water it caused the water concentration to lessen but the solute to increase. There are more water molecules going out of the cell than in the cell the cell membrane began to shrink known as dehydration. 2.
Explain, in detail, the process that caused these changes to occur. The elodea would not be able to live in salt-water environment because there is a greater concentration of the water in the cell. When there is salt in the cell, it would die. 3. Is this process reversible? If so, describe how you would reverse it? Yes, I think this process is reversible. You would have more of a salt solution then a water solution. Then you would add the water to the concentration then it will be revered