Egg Cell Macromolecules Lab

        In this lab we asked the question if, and which macromolecules can be identified in an egg cell. We have found that the egg membrane contained proteins; the egg white contained proteins and lipids; and the egg yolk contained monosaccharaides, lipids, and proteins. There was a small amount of monosaccharaides present in the egg yolk; it was rated 2/10 for the amount of color change which indicated a monosaccharaide present. There were no ploysaccharaides in any parts of the eggs. There were a lot of proteins in the egg parts; 5/10 in the egg membrane, 6/10 in the egg yolk, and 8/10 in the egg white. There were lipids in the egg yolk (3/10) and the egg white (1/10). I can infer from our Biology textbook and various vodcast notes, that the reason there are so many proteins is that proteins are scattered throughout cells in many places. The egg membrane contained proteins, and we know this because when sodium hydroxide and copper sulfate were mixed with the sample, it turned from blue to lavender. I know the reason the proteins were present is because proteins found in the cell membranes are transport proteins that allow certain molecules in and keep others out. There were also proteins found in the egg white, and I know this because when sodium hydroxide and copper sulfate were mixed with the sample, it turned from blue to a gradient of light to dark purple. The proteins were present in the egg white because enzymes (a type of protein) are scattered throughout cells for protection. Structural proteins also float around inside the egg white to be used as food for the developing chick. Proteins were also found inside the egg yolk, and I know this because when sodium hydroxide and copper sulfate were mixed with the sample, it tuned from blue to dark lavender. The reason proteins were present here is because enzymes are scattered throughout the cell. Enzymes make reactions happen, and the yolk is like the nucleus of the cell so it needs enzymes to function properly. Structural proteins would also be found in order to form the developing chick.
       Our data was unexpected because there were no lipids found in the egg membrane, which contradicts the data the textbook and lecture notes say (lipids are found in membranes). A cause for this outcome could be that the person measuring lipids may not have waited long enough for the contents to react with one another. The impact this experimental error had on the data was that it was inaccurate. We were unable to fully understand and discuss the lipids' presence in the egg membrane because the lipid test had errors. We also lost count of how many drops were put into a few test tubes. This could have been caused by dropping them too quickly and carelessly. This affected our experiment such that the results may be inaccurate. Because we added to many or not enough drops of the solution to test for the macromolecule, the results are inaccurate. We also forgot to label the test tubes and which one contained which part of the egg. This was caused by not reading instructions carefully. Luckily, the various egg parts were easily identifiable in this lab, but in other experiments the substances may have been mixed up and labeled inaccurately. Due to these errors, in future experiments I would recommend reading the directions carefully, as this seemed to be a common problem for my group. A second suggestion for improvement I have would be to slow down and make sure to do the lab correctly, so as to get the most accurate results possible.
      This lab was done to demonstrate which macromolecules were found and identified within an egg cell. From this lab I learned more in depth about why certain macromolecules were present in certain parts of the egg cell. This helped me understand the concept of the four macromolecules. I knew where each was located and what their textbook definitions were, however I did not know how to apply this information in a real life scenario. This lab helped me to understand how the macromolecules can be applied in everyday life. Based on my experience from this lab, I could now understand more about developing chicks and how they develop, where they get their nutrients from when they are in the egg, and why they need those certain nutrients (carbohydrates, proteins, lipids, nucleic acids).


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