Use positive and negative controls determine macromolecule

Put ml of corn syrup in a test tube Add 1ml of the Benedict Reagent, the solution will look blue Put the tube in a gently boiling water bath. First, we obtained a test tube rack and 5 test tubes. Between meals the liver breaks down glycogen to glucose and releases it into the blood stream to supply glucose to cells in need.

Summary The differentiation of bacteria into either the gram-positive or the gram-negative group is fundamental to most bacterial identification systems. Hair, fingernails, muscles, tendons, cartilage, enzymes, antibodies, hemoglobin, hormones, etc. First, we obtained a test tube rack with 4 test tubes.

The positive control color change will indicate which material the test reacts with. Using a low power objective, locate and focus on the cells. One gram of fat stores more than twice as much energy as one gram of carbohydrates.

Scientific Control Group

Counterstain is used to give a visible color to the gram-negative cells that were decolorized. Ask them which ones they expect to contain protein.

Methanol fixed smears of Staphylococcus aureus and Escherichia coli serve as the positive and negative controls.

Carbohydrates Carbohydrates are better known to students as sugars and starches.

Gel electrophoresis

Discuss where we get the materials from to build this structures and molecules inside of our bodies through our food. The amount of time required for decolorization will vary with the thickness of smear and the type of decolorizer used.

Would you like to make it the primary and merge this question into it. Fix the unknown smears using one of the two methods below. The first unknown, on the other hand, did not contain a reducing sugar because it did not change color after it was heated in the boiling water.

The crystal violet stain is susceptible to wash-out with water but not the crystal violet-iodine complex.


Starch and glycogen are carbohydrates. Table sugar disaccharide is a non-reducing sugar and does also not react with the iodine or with the Benedict Reagent. Identify a positive control test reaction for each macromolecule.

Testing for Macromolecules

It can also cleave a peptide from a synthetic substrate, yielding a chromophore p-nitroaniline which is yellow and can be measured photometrically at nm Iwanaga If the material is solid tell students to chop it finely or mush it in a mortar and add distill water before adding the reagent.

There are 20 different amino acids that combine to form polypeptides proteins. This step washes away unbound crystal violet, leaving Gram-positive organisms stained purple with Gram-negative organisms colorless.

Rinse the slide with a counterstain safranin or carbol fuchsin which stains all cells red. In contrast, controls are known solutions used to validate that the procedure is detecting what is expected and nothing more.

Prepare smears of unknown organisms in the empty quadrants on the slides. The tests can reveal hidden fats and sugars in food items and the relative amounts of fats, lipids and proteins in food can be determined.

Part 3 Unknown solution First, we obtained a test tube rack and 9 test tubes. We gently shook the test tubes, and observed the test tubes for color change. However, it is also central to phenotypic microbial identification techniques. Gram-positive organisms have a very thick peptidoglycan layer in their cell wall compared to that of gram-negative organisms.

Fatty acids are what make lipids non-polar and unable to dissolve in water. Introductory Gel Electrophoresis activity, students are introduced to the basic Size and net charge are factors that together determine how quickly molecules to the negative electrode and some to the positive electrode, depending on their overall charge.

Each of the known dyes will exhibit a unique gel. Bacterial Controls When doing a differential stain, it is best to use controls to help identify the stain reaction of the unknown bacteria.

Controls are types of bacteria that are known to show a certain, specific stain reaction.

Scientific control

Positive controls are things you do not change. for example; to see what kind of liquid a plant will grow faster in, your positive control is the plant, the rest you change and experiment with.

List 3 positive and 3 negative things about your Mustafa shopping experience? The use of positive and negative controls to determine the macromolecules present in an unknown solution. Course #Wednesday, PM, B Lab performed: September 21st, Introduction.

Every living thing is dependent on large complex molecules, known as macromolecules. The objective of this lab is to determine the macromolecule(s) present in each solution and use that information to identify the macromolecules(s) present in the unknown solution.

Many living organisms are composed of atoms that are linked together to make larger molecules known as macromolecules. The Molecular Composition of Cells Cells are composed of water, inorganic ions, and carbon-containing (organic) molecules. Water is the most abundant molecule in cells, accounting for 70% or more of total cell mass.

Use positive and negative controls determine macromolecule
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Testing for Macromolecules - Lab Report