Egg Cell Macromolecules Lab

      In this lab we asked the question: Can macromolecules be identified in an egg cell? We identifies which macromolecule was present in each part of the egg. We found that the egg membrane tested positive for lipids because it turned from red to orange in Sudan III. Lipids are found in egg membranes, because cell membranes, which are the equivalent of egg membranes, are made of phospholipid bilayers. We also found that the egg white contains protein because it turned the blue biuret solution purple. The egg white would contain protein because it is like the cytoplasm of a cell, which contains many proteins and ezymes, which are a type of protein. Finally, the egg yolk tested positive for protein because it turned the biuret solution purple. This is because the yolk is like the nucleus of the cell, which contains structural proteins.

     A possible error that could have occurred was two parts of the eggs accidentally mixing together. For example, if some of the egg white got into the beaker with the yolk, then the yolk may have tested positive for a macromolecule that was actually in the egg white. Another error could have been that there was not enough of each substance in the test tubes, so the color change may have been less drastic or obvious. This could make it seem like there was a smaller presence of the macromolecule, even when there was a lot of it. Due to these errors, I recommend devising an easier way to separate the different parts of the egg, and maybe have students put a larger amount of each part in the test tubes.

     This lab was done to demonstrate that different macromolecules are found in different parts of cells. This lab enforced the knowledge of where different macromolecules are found in the cell, which was taught in the vodcasts. For example, we found that the egg membrane had lipids in it, which was explained in the vodcast. This knowledge can help people know what they are getting from eggs. For example, body builders need protein to build muscle, so they can eat the yolk.