preview

Carbohydrates, Proteins, Lipids, and Nucleic Acid

Decent Essays

Carbohydrates, Proteins, lipids, and nucleic Acid Lab Exercise 6 Date: 9/17/12 Bio 102-11 Purpose the purpose of this experiment was to perform test to detect the presence of carbohydrates, proteins, lipids, and nucleic acids. Explain the importance of a positive and a negative control in biochemical test. Use biochemical test to identify an unknown compound. Background Most organic compounds in living organisms are carbohydrates, proteins, lipids, and nucleic acids they are called macromolecules. Each of these macromolecules is made of smaller subunits. These subunits are linked by dehydration synthesis. Dehydration synthesis is an energy requiring process in which a molecule of water is removing and the two subunits are boded …show more content…

Table 6.1 Solutions and color reaction for Benedict’s test for reducing sugars and 2 iodine test for starch | tube | solution | Benedict’s color reaction | Iodine Color Reaction | 1 | 10 drops onion juice | greenish | Brent orange | 2 | 10 drops potato juice | yellow | brown | 3 | 10 drops sucrose solution | Light blue | Dark brown | 4 | 10 drops glucose solution | Bright orange | No change | 5 | 10 drops distilled water | Light blue | No change | 6 | 10 drops reducing sugar solution | Light orange | No change | 7 | 10 drops starch solution | Light blue | black | (6.2)Material and Methods in the process or exercise of measuring the starch we were used the following material and how we used them to conduct the experiment. Obtain seven tubes the material to be tested table 6.1 and then add seven to ten drops of iodine to each tube, and then record the color of the tubes contents in table 6.1 Starch or amylum is a carbohydrate consisting of a large number of glucose units joined by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store. It is the most common carbohydrate in the human diet and is contained in large amounts in such staple foods as potatoes, wheat, maize (corn), rice, and cassava. Picture of starch molecules Table 6.1 tube | solution | Benedict’s color reaction | Iodine Color Reaction | 1 | 10 drops onion juice | greenish | Brent orange | 2 | 10 drops potato juice | yellow |

Get Access