Experimental Purpose: In this lab we are testing for monosaccharides disaccharides and polysaccharides. Monosaccharides are directly related to the tongues recognition of sweet things. This saccharides are very simple which allows your tongue to taste them. Disaccharides and polysaccharides on the other hand are too complicated for our tongues to pick up the sweet taste. All these saccharides are made of the same thing. Mono means one. Poly means many. These saccharides play a big role in our ability to taste. During our experiment we also used to chemical solutions. Iodine and Benedict's. Iodine turns your solution black once it recognizes a more complicated polysaccharide. And the Benedicts is just the opposite when the Benedicts recognizes …show more content…
Place tube in the hot water. After about 2-4 minutes in the hot water, check if the solution changed color. If the solution did change color to a more yellow, orange, brick red color, it is positive for the benedict's test. Positive for monosaccharides. Manipulated variable: The iodine and benedict's solutions. Responding variable: Whether the solution has monosaccharides, disaccharides or polysaccharides. Controlled variable: Same water temperature, same amount of water in beaker, same amount of the water in your solution, same amount of the benedicts and/or iodine added to the test tube per test. Experimental control: The color change of the solution caused by the benedicts or iodine solutions added to the mixture. Validity measurements: Our experiment results are very reliable. After every trial we always clean out the test tubes. And before we start our experiment we always set the hot plate to high. Results: As a result when we tested the tomato samples it was negative for the iodine test and positive for the Benedix test. This means that my hypothesis was correct and that tomatoes do contain monosaccharides. Sample Iodine Test Benedict's Test Tomato Negative
b) Benedict test the solution color will change from blue to pink/orange red, indicating simple sugars are present. Lugols test the solution color will change from yellowish brown to dark purple, indicating starch and polysaccharides are present. Sudan iV test the lipid content will turn into red, indicating lipids are
A monosaccharide is a carbohydrate that doesn’t hydrolize. A disaccharide is a group of that yield monosaccharides on hydrolosis. Lastly, polysaccharide is a carbohydrate that contains more than three monosaccharide units per molecule.
Monosaccharide are made up of one sugar unit, disaccharides are made of two sugar units, polysaccharides are long chains of sugar units.
4. We observed the test tubes and compared the colors produced from the reaction to the color palette in 1 minute intervals for 5 minutes total.
1. Fill in the table below with the results from the monosaccharide test experiment, and your conclusions based on those results.
Macromolecules are present in each of the five foods being tested which are pretzels, green peas, apple juice, biscuit mix and bacon bits. To determine this, reagents for the four macromolecules are being used which are Benedict’s, Iodine, Sudan IV and Biuret Solution. The independent variable in this experiment are the different foods being tested. The dependent variable in this experiment is the presence of the macromolecules.
Finally, the test tubes were placed in the the rack and we recorded the color of the solution for day one in table
Polysaccharides (e.g. starch and cellulose) are very large molecules that are connected by dehydrogenation (the removal of water) to form a covalent bond between a central carbon. (Reese, Et. Al., 2015) Simple sugars are detected by using Benedict’s test and the IKI test identifies if starch is
To conduct this test twelve test tubes, and a bottle with Biuret solution with an eyedropper is needed. Place two millimeters of the solution into a test tube. Add a full dropper of the biuret solution the test tube and mix the solutions by gently swirling the solutions. Repeat for each testable solution and record the results. Results: To interpret the results of the Benedict’s test, observe the color at which the solution becomes after being placed in boiling water in three minutes.
Use a pipette to mix Benedict’s Solution with the solution from the dialysis tubing. Then place the polysaccharide on the hot plate and wait to see if the solution changes color. Record observations. The initial mass of the dialysis tubing and beaker and the final mass & percent change : Data:
In conducting the experiment, four test tubes were set up; each containing 3 mL of distilled water, and 0.3 grams of baker’s yeast measured on a digital scale. The three independent variables tested were milk, starch, and sucrose. Milk is composed of the disaccharide lactose, along with unsaturated fats, and vitamins A and D. Starch, is a polysaccharide consisting of long chains of its monomer glucose. Lastly, sucrose, also a disaccharide, consists of one glucose molecule, and one fructose molecule. 0.3 grams of each were measured on a digital scale, and put into separate test tubes, along with a control tube that contained only water and yeast.
This is because glucose is the simplest type of carbohydrate (monosaccharide). However sucrose is a
Solutions and color reaction for Benedict’s test for reducing sugars and 2 iodine test for starch
During the Benedict's test, the contents of tube B did not change, indicating the absence of sugar in that particular substance. However, the contents of tube A did change orange indicating the presence of sugar in that substance. During the Lugol's test, the content of tube A did not change dark purple indicating the absence of starch in that substance However, the content of tube B changed to dark purple
1) Monosacchrides: Mono means single and saccharides refer to sugar. These are the simple form of carbohydrates that consists carbon, hydrogen and oxygen in the ratio of 1:2:1 (Ahmed 2014).