Once the students have completed the data collection, they will return to their seats to collaboratively complete the conclusion questions from the Student Answer Sheet.
For the iodine test, the three dimensional structure of various polysaccharides permits them to react with the iodine stain to produce a certain color. If the solution changes to a deep violet color then the solution is identified as a polysaccharide.
To demonstrate the process of hydrolysis, I break apart the disaccharide molecule and put the blue pop-beads back on the end of the monosaccharide models to represent the presence of hydrogen H atom and a hydroxide OH at the end of the model.
Students then place all of the labeled test tubes in a warm water bath on the hot plate assigned to their group.
Therefore, this is where all solutions are extracted in ethyl alcohol or as the control in the experiment. We will write a custom essay sample on Pre-lab: As for the Iodine stain, the color changes of bluish black indicated plant starch; cornstarch solution and unknown A3dark reddish brown indicated glycogenand violet brown to reddish brown indicated cellulose; potato solution and sweet potato presented positive test results for the different types of polysaccharides present.
The fatty acid chains can be carbon saturated with hydrogen atoms forming a straight chain without double bonds. There were many ranges of color changes in the Benedicts test and Iodine stain.
The video clip demonstrates student-group collaborative effort to analyze data and determine the identification of the unknown sugars. Oxidation occurs when a substance gains oxygen or loses electrons or hydrogen OIL — oxidation is loss and reduction occurs when a substance loses oxygen or gains electrons or hydrogen RIG — reduction is gain.
The hypothesis made for the outcome of the problem was neutrally correct. Students record their laboratory observations and data on the Identifying Carbohydrates - Student Answer Sheet.
The group is not excused from the lab area until their lab supplies have been cleaned and put away for the next group of students to use later in the day. Students are instructed to develop a conclusion statement on the back of their worksheet that summarizes what they did procedure and what they learned data analysis.
The assumption taken was that all form of sugars would have a present amount of reduced sugars while non-sugars did not for the Benedicts test.
Also, the distilled water test tube one served as a control for the experiment. Lab 2 Identifying Proteins and Lipids The Biuret solution is a blue liquid that changes to purple when proteins are present. Once the eight solutions have been prepared on the well plate, students place two drops of the iodine solution in each well.
The red and the yellow pop-beads represent the single monosaccharides that are now chemically bonded through the process of dehydration synthesis or condensation both terms mean to make or remove water. Soy flour and egg yolk, especially, have the highest protein.
The results turned out to have majority tests as negative or absent presence or polysaccharides.
For the Sudan III test, the hypothesis was all guessed correctly due to the common sense of variations of how protein holds for each solution.
Water tested pale blue, or negative, due to being the control of the experiment; as well as the unknown A3, buttermilk all lipidstable sugar processed sugar and honey all sugars.
This part of the test became a bit skeptical to figure out exactly what the unknown solution is. The water molecules blue beads are not pictured, but would have formed through this chemical reaction. In order to allow two monosaccharides to form a single disaccharide, the process of condensation or dehydration synthesis must occur by removing a hydrogen H atom and a hydroxide OH molecule to open up the binding sites to chemically join the two structures.
This chemical reaction removed a Hydrogen H and Hydroxide OH from the monosaccharides which opened up the binding sites so the two monosaccharides could chemically bond and the disaccharide to form. For the purposes of this activity, the water molecule that is removed will be represented by the blue pop-beads.
Pop Beads Disaccharide Model: Proteins are complex, specialized molecules composed of carbon, oxygen, hydrogen and nitrogen. Ethyl alcohol and egg white had none present. The following tested for low concentration pale color of lipids: For the iodine test, most of the educated guesses were wrong.
Instead, there was a low concentration that was resulted for the Biurets test. The red and yellow beads represent the monosaccharides single sugars. For the iodine test, it was resulted positive with a color change of bluish black that indicates it is a plant starch amylose type of polysaccharide; consisting of Carbohydrates Identification Lab Carbohydrates are an energy source or are used in making cell structures.
The first tests you will be doing will be designed to specifically test for carbohydrates a.k.a sugars. These are also called Pre-lab Questions.
Analysis: Lab 1 Identifying Carbohydrates There were many ranges of color changes in the Benedicts test and Iodine stain. For the Benedicts test, this oxidation/reduction response changes the arrangement of the reducing sugar creating a colored precipitate.
Analysis: Lab 1 Identifying Carbohydrates There were many ranges of color changes in the Benedicts test and Iodine stain. For the Benedicts test, this oxidation/reduction response changes the arrangement of the reducing sugar creating a colored precipitate. Identifying Biomolecules in Food – Pre Lab Background: Cells are composed of organic compounds called billsimas.com biomolecules include carbohydrates, lipids, proteins, and nucleic billsimas.com substances are used by your cells and often obtained through foods you eat.
Problem Statement. Students record their laboratory observations and data on the Identifying Carbohydrates - Student Answer Sheet. As the students are progressing through the activity, I rotate to each of the student-lab groups to ensure that the steps of the procedure are being followed and that the students have a strong understanding of how to analyze the.
Essay on Lipids and Carbohydrates; Essay on Lipids and Carbohydrates. Words 2 Pages. Lipids and Carbohydrates Lipids are a group of substances, which include fats, oils and waxes. Carbohydrates include sugars, starches, glycogen and cellulose. They are stored in plants as starches and in animals as glycogen.