PLEASE HELP Question 2
First, Demetri will test the three solutions containing milk (lactose).
He begins the experiment by preparing the lactase enzyme solutions. In one beaker he dissolves 1 lactase tablet in
100 mL of water at room temperature. He stirs the mixture until the tablet has dissolved completely. He repeats this
process in a second beaker, and then heats the beaker until the solution is boiling.
Demetri then tests these three milk (lactose) solutions for the presence of glucose:
• milk in water
• milk and lactase enzyme in water
. milk and heated lactase enzyme in water
Test Tube 1 - Milk (Lactose): Demetri fills the first test tube one-quarter full of milk. Then, he slowly adds water to the
milk until the test tube is three-quarters full. Using the stirrer, Demetri thoroughly mixes the solution. Then he inserts the
test strip for 30 seconds and records its color.
Test Tube 2 - Milk (Lactose) and Lactase Enzyme: Demetri fills the second test tube one-quarter full with milk. He then
adds the lactase-and-water solution until the test tube is three-quarters full. He uses a stirrer to thoroughly mix the
solution. Next, Demetri inserts the test strip for 30 seconds and records its color.
Test Tube 3 - Milk (Lactose) and Heated Lactase Enzyme: Demetri fills the third test tube one-quarter full with milk. He
then adds the heated lactase-and-water solution until the test tube is three-quarters full. After stirring, Demetri inserts
the test strip for 30 seconds and records its color.
According to the test strips, which of these milk solutions contained glucose?