IB Biology SL IA - 2190 Words

AP/IB Biology Lab Assessment The effect of various fruit and vegetable cell membranes on their water potential Independent variable: Type of fruit or vegetable. (Produce used: Russet potatoes, Pascal celery, Gala apple, Navel orange, and Imperator carrot). The fruit or vegetable will be placed in six 56.7 gram cups, ranging with sucrose molarities of 0 (distilled water), 0.2, 0.4, 0.6, 0.8, 1.0, with 5 trials, leading to 30 cups for each produce variable. Dependent variable: The water potential of the produce, found by placing the produce in different molarities of sucrose and finding the isotonic state of the produce with a plotted line graph. Controlled variables: The controlled variables include: The type of produce used:†¦show more content†¦Qualitative Observations: At the start of the experiment, all produce appeared in normal condition, and all of the sucrose solutions had settled and looked normal, although the 0.2-molarity sucrose had a small amount of mold in the interior of the bottle. In the middle of the experiment, all produce samples were placed in their correct cups and were covered with aluminum foil. In order to keep the experiment controlled, we did not remove the aluminum foil until the produce had soaked for two days and was ready to be weighed. At the end of the experiment, we noticed a majority of the produce, especially apples, became soft and turgid in the solutions of distilled water, 0.2-molarity sucrose, and 0.4-molarity sucrose, as following to the fact that we noticed the majority of the produce gained weight (in grams) in those solutions. We also noticed produce, especially potatoes, in the solutions of 0.6-molarity sucrose, 0.8-molarity sucrose, and 1.0-molarity sucrose grew mold, which was peculiar because every potato sample in the 1.0-molarity sucrose lost an average of 25 percent in mass. Analysis of data: As shown by the graph and tables, the averages of percent change in mass showed the potato samples increased mass in the control, distilled water, and 0.2-molarity sucrose. The potato samples also lost considerable mass in 0.4-molarity sucrose, 0.6-molarity sucrose, 0.8-molarity sucrose, and 1.0-molarity sucrose. The data is