Question

HELP PLS 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?

Answer 1

Answer:

2nd test tube, because test strip color turned to green, which indicates this test tube solution contained glucose.

Explanation:

Lactase will break down the lactose into glucose and galactose. In first test tube there is no such activity because there is no lactase presented.  In 3rd test tube as the enzyme is heated so it is get decomposed so in this case also there is no activity of lactase enzyme.

Answer 2

The second tube is the tube that contained glucose.

We can arrive at this answer because:

• Lactase is a protein.
• This protein has the function of breaking lactose into smaller molecules, which are glucose and galactose molecules.
• This protein is sensitive to high temperatures and loses functionality in very hot environments.

In the case of the tests used in the question above, we can say that in the first test tube, the lactase solution was not added, so the lactose was not broken down. The lactase solution was added to the second test tube, where the lactose was broken down generating glucose and galactose. In the third test tube, the heated water prevented the lactase from acting and therefore it cannot break down the lactose.

Therefore, only the second tube has glucose.

More information:

https://brainly.com/question/13129?referrer=searchResults