Introduction:Carbohydrates are molecules that contain Carbon, Hydrogen, and Oxygen. The most basic sugar- carbohydrate is the monosaccharide. Carbohydrate molecules are categorized by the number of carbons present in the molecule. Glucose, the most common monosaccharide has six carbons per molecule, which is called a hexose. Carbohydrates also have a 2:1 hydrogen to oxygen ratio. This aids in the condensation and hydrolysis reactions.
A condensation reaction occurs when two monosaccharides join by the removal of H2O. During condensation synthesis one monosaccharide losses an OH and the other losses a H. As a result the two monosaccharides bond by forming maltose a disaccharide with a by-product of a free H2O. When three or more monosaccharides or monomer are involved in a condensation synthesis a polymer or polysaccharide is formed with a by product of water. Starch and Glycogen are two common chain polymers.Just as the removal of water joins carbohydrates together via condensation synthesis, hydrolysis is the reaction using water to break apart Di and polysaccharide.
A Di-saccharide is bound by sharing an oxygen with one hydrogen on each opposing side. When H2O is re-introduced via hydrolysis the two monomers in the disaccharide no longer need to share one H2O, and as a result the opposing sides absorb the OH and H and break apart. This reaction is a common theme in the digestion of complex carbohydrates.Experiment 3: Test for SugarsWe will test five different solutions for presence or absence of reducing sugars using a premixed Benedict's reagent. These dependent variable solutions will be water, glucose , onion juice, potato juice, and starch suspension. When the Benidict's reagent is combined with sugars at a boiling temperature, a color reaction will occur. Our independent variable, Benidict's reagent color is blue.The negative control will be the combination of water and Benidict's reagent.
This sample will undergo all the steps of the test except for the one being tested for i.e. sugars. If the end result is negative color change (blue) , it will thus be determined that the experiment and the Benidict's reagent is not contaminated and the experiment may proceed. The negative control will also serve as a comparison to gauge against the color change in the other four sugar tests.EXPERIMENT 3: Test for Sugars: TESTS MAT. & METHODS HYPOTHESIS RESULTSTube 1 1cm water+2cm Benidict's reagent.
No color changeNegative control no color change. Neg-sugar. BlueTube 2 1cm glucose solution+ 2cm Benidict's reagent.
Briefly describe an alternative technique that could be used to measure the amount of glucose within sports drinks. (5 points)
When the solution remains the same, it means the solution is negative control and does not have sugar. The presence of starch can be detected by using the Lugol’s iodine solution. If the unknown A, B, C milk samples turn to a dark blue color during the Lugol’s test, then these samples are positive control and also contain starch in them. But if the solutions turn to yellowish brown, it means these solutions are negative control
To uncover organic compounds like carbohydrates, lipids, proteins and nucleic acid, by using tests like Benedict, Lugol, Biuret and Beta Carotene. Each test was used to determine the presents of different organic molecules in substances. The substances that were tested for in each unknown sample were sugars, starches, fats, and oils. Moreover, carbohydrates are divided into two categories, simple and complex sugars. Additionally, for nonreducing sugars, according to Stanley R. Benedict, the bond is broken only by high heat to make make the molecules have a free aldehydes (Benedict). As for Lipids, there are two categories saturated and unsaturated fats. One of the difference is that saturated fats are mostly solids and have no double bond (Campbell Biology 73). The Beta Carotene test works by dissolving in a lipid, thus giving it color to make it visible. Moreover, proteins are made out of amino acids that are linked by a polypeptide bond (Campbell Biology 75). The purpose of this experiment was to determine whether an unknown class sample or food sample had any carbohydrates, lipids, or proteins in it. The expected result of the lab was that some substances would be present while other would be absent.
For the first biuret test, approximately 10 drops of water were added to the test tube. After the water was inside of the test tube, 10 drops of 5M NaOH and 5 drops of the Biuret reagent solution was added. The test tube was then gently rolled by a member of the group to mix the solution and everyone recorded the color of the solution. The same procedure was followed to test for starch, protein, sugar, lipid, and the unknown, but instead of the initial 10 drops of water, a sample of the variable being tested was placed in the test tube.
For the lab experiment for Membrane Damage, we tested the extract pigment and diluted it. When the pH solutions are added, this will cause it to be in a range of absorbance. We used materials as follows. Obtaining a beet we proceeded to cut small individual cubes. We then rinse each cube to remove any damaged pigments with deionized water. Using a blender, we blend the beets with 15 mL of pH 7 DI water. After blending we used cheesecloth to separate the liquid from the solids for easier centrifuge process. Then we put the liquid beet into a centrifuge tube and centrifuge it for 5 minutes at 2500 rpm. We then remove the supernatant into a beaker, and discarded the sediment. Using a 1:4 ratio mixture of the supernatant and deionized water, we made a stock solution. We then tested the stock solution’s absorbance with a spectrophotometer, and place 1 mL of the solution into separate test tubes. Next we added an additional 4 mL of pH solutions in the 2-11 range into each test tube. After mixing, we tested the absorbance for each solution using a spectrophotometer.
The independent variable for this experiment is the enzyme concentration, and the range chosen is from 1% to 5% with the measurements of 1, 2, 4, and 5%. The dependant variable to be measured is the absorbance of the absorbance of the solution within a colorimeter, Equipments: Iodine solution: used to test for present of starch - Amylase solution - 1% starch solution - 1 pipette - 3 syringes - 8 test tubes – Stop clock - Water bath at 37oc - Distilled water- colorimeter Method: = == ==
The progress of this reaction was monitored using Dinitrosyl alcohol. (DNS) as the reagent reacts with the reduced sugar products. The The colour of DNS changes from yellow to varying shades of red depending on the color of the DNS. on the on the reducing sugars product being found with time. The light absorption from the varying colours of solutions can then be measured calorimetrically.
Experiment #3: The purpose of this experiment to test the chromatography of plant pigments the alcohol test strip test will be used.
When I dropped iodine to the leaf where I split off from the plant which had waited in red light, its color changed into blue. However, when I dropped iodine to the leaf where I split off from the plant which had waited in green light, its color stayed the same. It is because the plant waited in red light could make more photosynthesis than the other one, so it has more glucose and an iodine solution makes substance’s color blue if it has starch. It is used to test the presence of starch.
Carbohydrates are categorised in three many groups: Ø Monosaccharide – monomers and therefore contain single surgar. Ø Disaccharide – contain double sugars. Ø Polysaccharide – are large molecules containing many complex sugars. The general formula for carbohydrates is Cx(H20)y. Monosaccharides are white crystalline solids with low molecular mass and sweet tasting.
An error that occurred in the experiment was during the ceric nitrate test because solution 4 should have produced a color change. During a base hydrolysis of aspartame, aspartic acid, phenylalanine and methanol are produced, therefore the ceric nitrate test should have been a positive for alcohol. A reason that this could have shown a negative result is because methanol is a volatile substance and it could have evaporated out, which would have caused a negative ceric nitrate test
Starch, cellulose, glycogen, and chitin are all examples of polysaccharides. According to the BIO 1510 Lab Manual (2016) polysaccharides are not very soluble in water but can be made to go into solution through heating or agitation. Polysaccharides are excellent energy storage molecules because they are easily built and broken down by enzymes. Forming fairly compact structures, polysaccharides allow energy storage without the space required by a pool of free glucose monomers. Other polysaccharides form strong fibers that provide protection and structural support in both plants and animals. (Carbohydrates.” Home,
The Benedict's Test is used to test the presence of simple sugars in a sample. If sugars are present, a color change will occur from blue to red. However, although the Benedict's test shows the presence of sugars, it cannot accurately determine the concentration of sugar in a sample solution. In our method, we added specific concentrations of glucose to the Benedict's test to use as a chart to estimate the glucose concentration of an unknown solution X. Although this gives a rough estimate of the concentration, it is very inaccurate. For example, the mystery solution X was a pale orange color, which was between the colors in my first and second test tube.
The primary method to control gestational diabetes mellitus (GDM) is through dietary regulation. The most effective method to control GDM via diet is through carbohydrate restriction and/or selectivity. It is recommended that pregnant women with GDM reduce their carbohydrate intake to 40% of the total caloric intake or can maintain a 60% carbohydrate intake but those carbohydrates must all come from low glycemic index foods. Examples of low glycemic foods are apples, spinach, black beans, split peas, oatmeal, and quinoa. Additional suggestions are to eat complex carbohydrates instead of simple, refined sugars. Eat small, frequent meals and snack often in between meals in order to maintain constant glucose levels throughout the day.
Carbohydrates are divided into two groups, simple carbohydrates and complex carbohydrates. Simple carbohydrates, sometimes called simple sugars, include fructose (fruit sugar), sucrose (table sugar), and lactose (milk sugar), as well as several other sugars. Fruits are one of the richest natural sources of simple carbohydrates.