Biologically Important Molecules
Carbohydrates, Proteins Lipids
And Nucleic Acids
Professor Anthony Depass
By completing lab exercise 6 : Biologically Important Molecules, we are able to perform tests such as the Benedicts Test for Reducing Sugars, Iodine Test, Biuret Test, Sudan IV Test, and lastly the Grease-Spot Test that detect the presence of biologically important carbohydrates, protein lipids and nucleic acids. Most known compounds in living organism are if fact carbohydrates, lipids, proteins, and nucleic acids. Each of these macromolecules are tested differently. The Benedicts test identifies reducing sugars based on their ability to reduce cupric ions to cuprous oxide at basic pH resulting in a green to reddish orange color. The basis for the iodine test for starch is since starch is a coiled polymer of glucose, the iodine interacts with the coiled molecules turning bluish black. The Biuret test, tests for proteins by checking if there are the presence of long chain polypeptides, in doing so cause a color change of violet. The Sudan IV test for lipids is based the it lipids ability to absorb pigment such as the Sudan IV
Materials and Methods:
Obtain seven labeled test tubes, and add each material being tested to its own test tube. Then add 2mL of benedict solution to each tube and place the test tubes in a gently boiling water bath for 3 minutes...