Tests To Detect The Presence Of Carbohydrates, Proteins And Lipids

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All living things contain organic molecules such as lipids, carbohydrates, proteins and acids. In order to detect the presence of carbohydrates, proteins and lipids we have to do experiments.
The Iodine test is used to detect the presence of carbohydrates. This test is used to distinguish starch (polysaccharide) from carbohydrates. Reaction between starch and Iodine produce a dark grey, black color and it means that the test is positive. A yellow color means that test is negative. But other polysaccharides may give other colors including blue or red.
In order to detect the presence of glucose (monosaccharide) we have to use a Clinitest tablet. Clinitest tablets are usually used for urine sugar testing. If
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But tube B2 (glucose) turned color to purple after we added Clinitest in it. This is means that test is positive for glucose and will be positive for other monosaccharide’s as well. The reaction is negative for starch and water.
In the Experiment 2 after we added Biuret’s reagent to the tube A (Albumin) we could see that due to reaction color turned to purple. So, then we added Biuret’s reagent in tube B (starch) and color stayed blue. We can say that reaction between Biuret’s reagent and Albumin is positive and between Biuret’s reagent and starch is negative. Reaction didn’t work with starch because it doesn’t contain peptide bonds. Once Albumin turned purple we can say of protein presence.
In Experiment 3 at the beginning we added water into the tube and then salad oil into the same tube. After we mixed it we noticed that oil still on top of the water. Then we added a few grain of Sudan IV. We covered a tube and mixed. When we added Sudan to a mixture of lipids and water the dye moved into the lipid layer and we got a reaction between salad oil and Sudan IV due to which color on top turned red but at the bottom where is the water stayed clear. We can say that reaction worked between salad oil and Sudan IV to detect a presence of lipids. Reaction with water is negative.

We performed these experiments in order to detect the presence of carbohydrates, protein and lipids which are important molecules in person’s