Biology: Chemical Tests and Test
Biology 100 Lab
Laboratory Report
Title: Identifying the four major classes of macromolecules through various tests.
Group Members: Antonia Johnson, Payton Ewing, Lenneisha Hepburn, Kendisha Hanna, Introduction: Macromolecules also known as biological molecules are monomers which are the simple units of polymers. All macromolecules contain carbon and hydrogen which are found in organic compounds. In this Experiment we will test for the presence of protein, starch, lipids, and sugars by analyzing the content off food and / or other substances by utilizing different testing methods. In the scientific method, a chemical test that is sensitive to these groups can be used to identify molecules that are in that class. Testing involves many procedures that are very precise. This lab is broken down into five different sections; we will be using the Biuret Test for amino groups present in proteins. The Iodine Test to identify the presence of starch. The Grease Spot Test and the Sudan Dye test to identify the presence of lipids (fatty acids). The Benedict’s Test to identify the presence of reducing sugars.
In the biuret test if the test result for protein changes a color of lavender, purple or pink, the test result for protein is positive using the Biuret reagent. In the iodine test If the Iodine turns black or blue-black there is starch present so the test result is positive. In the grease spot test if the test results leaves a translucent mark on the unglazed paper it is positive for the presence of lipids. In the Sudan test if the globules have red dye within them the test result is positive; this means there is lipids present in this test. For the Benedicts test if the substance turns from a blue liquid to a greenish to yellow/orange/red shows the presence of a reducing sugar. BENEDICT'S TEST
Introduction: Monosaccharaides and disaccharides can be detected because of their free aldehyde groups, thus, testing positive for the Benedict's test.
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Laboratory Report
Title: Identifying the four major classes of macromolecules through various tests.
Group Members: Antonia Johnson, Payton Ewing, Lenneisha Hepburn, Kendisha Hanna, Introduction: Macromolecules also known as biological molecules are monomers which are the simple units of polymers. All macromolecules contain carbon and hydrogen which are found in organic compounds. In this Experiment we will test for the presence of protein, starch, lipids, and sugars by analyzing the content off food and / or other substances by utilizing different testing methods. In the scientific method, a chemical test that is sensitive to these groups can be used to identify molecules that are in that class. Testing involves many procedures that are very precise. This lab is broken down into five different sections; we will be using the Biuret Test for amino groups present in proteins. The Iodine Test to identify the presence of starch. The Grease Spot Test and the Sudan Dye test to identify the presence of lipids (fatty acids). The Benedict’s Test to identify the presence of reducing sugars.
In the biuret test if the test result for protein changes a color of lavender, purple or pink, the test result for protein is positive using the Biuret reagent. In the iodine test If the Iodine turns black or blue-black there is starch present so the test result is positive. In the grease spot test if the test results leaves a translucent mark on the unglazed paper it is positive for the presence of lipids. In the Sudan test if the globules have red dye within them the test result is positive; this means there is lipids present in this test. For the Benedicts test if the substance turns from a blue liquid to a greenish to yellow/orange/red shows the presence of a reducing sugar. BENEDICT'S TEST
Introduction: Monosaccharaides and disaccharides can be detected because of their free aldehyde groups, thus, testing positive for the Benedict's test.
Such
References: * http://en.wikipedia.org/wiki/Scientific_method * http://biology.unm.edu/ccouncil/Biology_124/Summaries/Macromol.html * Principles of Biology Laboratory Manual 2007 prepared by: Chisholm-Lightbourne