BIO SCAN:  Milk is a substance that is full of protein, vitamins, minerals and water. When milk is ingested, one of the things that happens in humans is that blood glucose levels rise. Brainstorm some of the ways that drinking milk could cause changes in blood glucose levels.

MILK MADE EQ: How are materials broken down into their component parts and recycled in biological systems?

Part 1: What’s In Milk?  Prediction: Make a prediction as to whether milk will have glucose in it or not.  Materials: well plate, pipet(s), glucose test strips, whole milk, 2% glucose solution.  Procedure: Design a procedure to test for the presence of glucose in milk. Write a numbered list of steps.  Results: Is glucose present in milk?  Analysis: Based on your results, what else do you need to know? Describe what would you like to investigate next?

But, there’s no glucose in milk...  If there is no glucose in milk, where did the glucose come from that caused a rise in blood glucose levels after ingestion?  What may have happened to the milk after it was ingested?  How does that work?

PART 2: ENZYME INVESTIGATION Initial Color (+ / -) Color after 2 minutes (+ / -) Glucose Solution ++ Milk -- Lactase Milk & Lactase

PART 2: ENZYME INVESTIGATION Procedure 1. Add 1 drop of lactase to an unused well. 2. Add 1 drop of lactase plus two drops of milk to an unused well and mix with toothpick. 3. After 3 minutes, test each of the above for the presence of glucose by dipping a piece of glucose test paper to each. Record results. 4. After 2 minutes note any color change in the glucose test paper and record the results in the data table. Answer the following questions in your journal. 1. What did you test? 2. What did you learn? 3. Back to the original question, why does milk cause a person’s blood glucose level to increase?

CLEAN UP  Return all three beakers with their respective pipet to the counter.  Return unused glucose test strips to the counter.  Throw out used test strips.  Wash your well plate.  Return goggles  Clean table.  Wash your hands

Clean Up – Last Period  Wash all three beakers and throw out their respective pipets.  Return unused glucose test strips to the counter.  Throw out used test strips.  Wash your well plate.  Return goggles  Clean table.  Wash your hands

WRAP-UP DISCUSSION LACTASE C 12 H H 2 0 C 6 H C 6 H Heat Energy Lactase

DISCUSSION QUESTIONS 1. Explain how lactase caused the milk to test positive for glucose. 2. Could you get glucose from milk without lactaid? Explain. 3. Describe the equation below. What are the reactants, products, and why is lactase written on the arrow. 4. Is this a decomposition or synthesis reaction? 5. Where are the monomers? In the reactants or products? 6. Based on what you now understand about enzymes, why might they be necessary for life?

EXIT ASSESSMENT  Milk is a substance that is full of protein, vitamins, minerals and water. When milk is ingested, one of the things that happens in humans is that blood glucose levels rise. How does drinking milk cause changes in blood glucose levels.