GREAT FOR CHEM, BIO CHEM, and BIOLOGY!!
In this inquiry driven lab, students will perform 4 procedures to test for lipids, proteins, reducing sugars, and starches. In part 1 students will perform controlled tests (Iodine test for starches, Biuret test for protein. Benedict's test for reducing sugars and the Grease spot test for lipids) on controlled food items that will test positive for only one biological molecules (albumen, corn starch, glucose, distilled water, and plant cooking oil). Students will make positive test statements in the form of if/then hypotheses they will apply in Part 2. For part 2, students will bring in food samples to test as "unknowns" to see what biological molecules are present in the food.
You will be purchasing the fully accessible Word document to modify for use in your classroom. However, I maintain the copyright, as this lab is part of a lab workbook in the process of being published.
Supplies needed per group (this can be done pretty micro-scale with small amounts of supplies):
500 mL beaker, hot plate, 8 test tubes, test tube rack, IKI, Biuret Reagent, Benedict's solution, brown paper bag or those paper-y brown paper towels, corn starch, albumin, glucose, distilled water, vegetable oil. Students are instructed to bring in 2 small food samples (clear colors work best). You can also set up solutions for students to compare intensity of different biological molecules such as comparing non-fat versus regular yogurt or salad dressing to see how fat-free has more sugar. Milk works well because it is the only animal food that contains sugar.