Question

The Enzyme Lactase experiment design

Material required:

Skim milk, lactase drops, test tubes, glucose test strips, eye dropper, mixing spoon, graduated cylinder

Step:	Why this step is important:

If you actually conducted this experiment, what safety issues would you need to identify?

If you actually conducted this experiment, what appropriate precautions would you take to ensure that you performed the experiment safely?

If you actually conducted this experiment, what results would you expect to see?

Answer 1

The principle of the experiment is-

Lactase is an enzyme which catalyzes the hydrolysis of the disaccharide lactose into the monosaccharides galactose and glucose. Humans require lactase for digestion of lactose found in milk and other dairy products.

In this experiment, we will monitor the activity of the enzyme lactase by determining how much glucose is formed because glucose is a product of lactose hydrolysis by the enzyme lactase. We will monitor the enzyme activity using test strips that measure the level of glucose in the reaction mixture. The presence of glucose in solution will change the test strip from yellow to a blue-green color.

Method-

1) Prepare the following reaction in three test tubes-

A) Test tube with skim milk and enzyme solution (lactase). This is the test solution.

B) Test tube with skim milk and distilled water. This serves as negative control as this would not produce glucose

C) Test tube with glucose. This serves as positive control.

2) Time for 2 minutes and test for glucose with the glucose test strip.

Test tube A- strip will be Blue green color as lactase converts lactose into glucose and galactose

Test tube B- strip will be yellow colour as no glucose is formed due to the absence of the enzyme lactase.

Test tube C- strip will be blue green colour as there is glucose as a control in it.