Our group asked the question "How and why does a cell's internal environment change, as its external environment changes?" Through our data, we found that a cell's environment changes because of osmosis, depending on what environment it is currently in. When taking the Egg Diffusion lab, our group left one egg in de-ionized H20, while the group we teamed up with left an egg in sugar water, measuring their circumference and mass beforehand. After one full day, our groups checked on our eggs, measuring their circumference and mass once again. With the ending of our experiment, our groups found that the egg in sugar water shrank, while the egg in de-ionized water grew, its mass shrinking -0.44%, while its circumference grew 7.78%. This came to be because of osmotic pressure, where a cell will adjust to its environment by giving up or absorbing water in order to balance out the solute.
This change was caused from osmosis, a passive diffusion where the solvent (water) either diffuses into or out of the cell membrane in order to balance the concentration ratio of water to sugar, the solvent. This happens as the solute cannot diffuse across the cell membrane. In the case of the sugar water egg, the solvent was greater outside of the egg, and it shrank in order to balance out the ratio, making a change from low concentration to high concentration. In turn, this put the sugar water egg in a hypertonic environment, where there is more solute outside the cell.
This lab can be related to many real life events, one of them being how your skin "prunes" up after you are in the pool for an extended period of time. Osmotic pressure makes your skin bloat up as water seeps in, making your skin look "pruned".
From this experiment, I have better learned about the principles of osmosis, and the effects of osmotic pressure. In fact, I can make my own experiment from this, further testing this principle by putting an object relative to the egg used in the previous lab, draining its solvent in a hypertonic environment, then putting it in a hypotonic environment full of solvent, and seeing if the object grows once again.
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