Elodea Experiment Lab Report

1) Hypothesis and Null Hypothesis for experiments

For the experiment involving the red blood cells, the proposed hypothesis is that if blood cells are placed into a hypotonic solution of distilled water, then the cells will undergo a process called hemolysis where they swell and burst. For this experiment, the null hypothesis is that if blood cells are placed into a hypotonic solution of distilled water, then the cell will not undergo hemolysis.

For the experiment involving the elodea plant, the hypothesis is that if the leaf of an Elodea plant is placed into distilled water, then the cells will become turgid, but will not burst because of the cell wall. The null hypothesis for this experiment is that if the leaf of an elodea plant is placed

This is because the cells were still completely intact. The blood that was mixed with the 0.9% salt concentration and 0.5ml of distilled water also appeared to be foggy at the end of the experiment since this would be an isotonic mixture. However, the blood that was mixed with 1.00ml of distilled water and no salt is the most transparent at the end of the experiment. When observing the leaf that was placed in the distilled water, the contents appear to be spread out completely against the cell wall and the wall appears to be swollen and hard. In this cell, the large central vacuole is observed to be completely filled with water. The cells of the leaf placed in the 0.9% saline solution appear to be less swollen but still full. When observing the leaf that was placed in the 5% saline solution, cells appear shriveled up on the inside of the cell wall. In these cells, the central vacuole cannot be seen at all.

3)

Due to this, the blood that was placed in distilled water (the hypotonic solution) appears to be transparent. This is because there was very little if any hemoglobin left in the cells since they all had hemolysis. This is the same reason that the cells in the .9% saline solution and the 1.8% solution appeared to be foggy, this is because their cells did not show hemolysis and they therefore still have all the original hemoglobin present. Therefore, the hypothesis was correct, because the blood that was placed in distilled water ruptured and showed hemolysis.

The plant cells that were placed in the hypotonic solution (the distilled water) appeared to be turgid because they looked hard and swollen. However, this cells did not burst like the animal cells because of the presence of the cell wall. The cells that were in the hypertonic solutions (5% saline) appeared to be shriveled up because the water was removed from them, which is the same thing that happens in animal cells. Therefore, the hypothesis is correct because the cells that were in distilled water became turgid but did not show