BIOLOGY-FGS0044
LAB REPORT 3.1 : CARBOHYDRATE DETECTION TEST
LAB REPORT 3.2 : PROTEIN DETECTION TEST
LAB REPORT 3.3 : LIPID DETECTION TEST
GROUP MEMBERS :
CONTENTS
NO. | TITLE | PAGE | 1 | INTRODUCTION | 3 | 2 | LAB 3.1 : CARBOHYDRATES DETECTION TEST | 5 | 3 | LAB 3.2 : PROTEINS DETECTION TEST | 8 | 4 | LAB 3.3 : LIPIDS DETECTION TEST | 12 | 5 | REFERENCES | 14 |
INTRODUCTION
Carbohydrates (saccharides) are molecules consist of carbon, hydrogen and oxygen atoms. A major food source and a key form of energy for most organisms. When combined together to form polymers, carbohydrates can function as long term food storage molecules, as protective membranes for organisms and cells, and as the main structural support for plants and constituents of many cells and their contents. Carbohydrates are tests by using Molisch’s test and Benedict’s test.
Molisch 's test is a sensitive chemical test for the presence of carbohydrates, based on the dehydration of the carbohydrate by sulphuric acid to produce an aldehyde, which condenses with two molecules of phenol, resulting in a red- or purple-colored compound.
Benedict 's test allows for the detection of the presence of reducing sugars (sugars with a free aldehyde or ketone group). All monosaccharides are reducing sugars since all of them have active carbonyl group. Some disaccharides that are exposed to a carbonyl group are also reducing sugars but less reactive than monosaccharides. By mixing the sugar solution with Benedict’s solution and heating them, a redox reaction will occur. The copper (II) sulphate present in Benedict’s solution reacts with electrons from aldehyde or ketose group of reducing sugars to form cuprous oxide, a red brown precipitate.
Proteins are inherently important to any living organism. They control cell process, provide support, and transport substances within a cell. They can even take the form of enzymes and hormones, regulating
References: 1. http://biolabprotocolsden.blogspot.com/2013/03/color-reactions-of-lipids.html 2. http://www.scribd.com/doc/51265337/Lipids-Chemical-Test 3. http://en.wikipedia.org/wiki/Molisch 's_test 4. http://en.wikipedia.org/wiki/Ninhydrin 5. http://en.wikipedia.org/wiki/Benedict 6. http://en.wikipedia.org/wiki/Tyrosine 7. http://www.livestrong.com/article/402210-which-kind-of-amino-acids-are-in-egg-whites/ 8. http://homepages.ius.edu/dspurloc/c122/casein.htm 9. http://pubs.acs.org/doi/abs/10.1021/ac60312a003?journalCode=ancham 10. http://wiki.answers.com/Q/What_is_the_reaction_between_glucose_solution_and_Benedict 's_solution