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Dissolve 180.2 g of glucose in 500 mL of distilled water using a stir bar. Once the solute has dissolved in the smaller volume of solvent, increase the total volume to 1 L. This creates a 1 M glucose solution suitable for macromolecules identification using indicator solutions.

Boil 1 L of distilled water on a hotplate. Make a paste by mixing 8 g of cornstarch with 10 mL of cold water. Dissolve the cornstarch paste into the boiling water, stirring until fully incorporated. This produces a 10% cornstarch solution for experimental use.

Combine 1 g of gelatin powder with 1 L of distilled water. Use a hotplate to boil the solution, monitoring carefully to prevent burning. Continue heating until the gelatin has completely dissolved, creating a uniform 10% gelatin solution for your macromolecule experiment.

Labeling beakers with source material names and corresponding images ensures accurate identification of each solution throughout the experiment. Clear labels prevent cross-contamination and experimental errors, allowing students to track which macromolecule source is in each beaker during testing and analysis.

Always wear gloves, goggles, and a lab coat when handling reagents such as iodine, which can stain clothes and skin. These protective measures minimize exposure to potentially harmful chemicals and prevent contamination of your workspace, clothing, and personal items during lab work.

After filling each beaker with its designated solution—250 mL of glucose, cornstarch, gelatin, or vegetable oil—cover all beakers with laboratory film. This prevents contamination, evaporation, and oxidation of the solutions until the activity is ready to commence and testing begins.

Beaker A contains glucose solution representing carbohydrates from the entire corn plant. Beaker B holds cornstarch solution representing stored carbohydrates in the corn kernel. Beaker C contains gelatin solution representing proteins from bone. Beaker D holds vegetable oil representing lipids from soybeans.