Chemical Composition of Cells
Testing for Proteins:
The independent variable is the biuret reagent. The dependent variable is the solutions being used as follows; distilled water, albumin solution, and starch solution.
If the protein is present, then the biuret will change to a violet color.
Authors: Eliza Koundry and Jody Cote
Eliza was in charge of adding equal amounts of biuret reagent to the distilled water, albumin solution, and the starch solution. Jody was in charge of recording any color changes in the appropriate tables.
Testing for protiens: For solutions we used; water, albumin, and starch. We added equal amounts of biuret reagent the (independent variable) to the distilled water, albumin solution, and starch solution (the dependent variable) to see if protein was present. If protein is present the distilled water, albumin solution, or the starch solution will change to a violet color.
The hypothesis is that protein will be present in the albumin and the starch when you add the biuret reagent, but not in the water. Since water is such a basic solution and is composed of one oxygen atom and two hydrogen atoms, protein would not be present. I felt it would be present in the starch solution and the albumin solution.
Materials and Methods:
Materials in this lab are as follows: Distilled water, albumin solution, starch solution, and biuret solution, 3 test tubes labeled 1, 2, and 3, (each number representing the distilled water, albumin solution, and starch solution), and a waxed pencil to do the labeling of the test tubes.
Number three clean test tubes with a waxed pencil. Add equal amounts of biuret reagent to (1) distilled water, (2) albumin solution, and (3) starch solution. Record any change of color.
Since the albumin solution turned a violet color we found that there is protein present. The distilled water and the starch contained no protein....
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