Macromolecule Lab Report

A macromolecule is a molecule that contains any "large number" of atoms. There are four main different categories of macromolecules that make up our body: carbohydrates, lipids, proteins, and nucleic acids. (1) Carbohydrates are sugars that store and transport energy. (2) Lipids also store energy and also are signalling molecules. (3) Proteins are linear chains of amino acids that help with the structure, function, and regulation of the body’s tissues and organs. (4) Finally, Nucleotides make up our DNA strands and are divided into pyrimidines, and purines depending on the structure of their nitrogenous bases. This lab’s purpose is to learn chemical tests for organic molecules including sugars, starch, and protein. Furthermore, it is required to perform tests, such as the Iodine, Benedict, and Biuret tests, on known solutions of the organic compounds listed to learn their positive tests and, afterwards test different …show more content…
The tests performed on each compound are the Iodine test, Benedict test, and Biuret test. Each of these tests help identify different organic compounds. First off, The iodine test is performed to test for the presence of starch in different foods and compounds. When iodine is mixed with starch in water, an intensely coloured starch/iodine compound is formed. Starch consists of 20-25% Amylose and 75-80% Amylopectin. The iodine gets stuck in the coils of beta amylose molecules and results in the mixture. There is some transfer of charge between the starch and the iodine. That changes the way electrons are confined, and so, changes the arrangement of the energy levels. These new energy level arrangements absorb visible light- giving the compound its intense bluish/purple color (How does starch indicate iodine, 2013). If iodine is, however, mixed with a compound that doesn’t contain starch, there would be no visible