Question

Question 3 A Amylase is a protein that catalyzes the conversion of starch to simple sugars. Amylase activity in an aqueous solution can be measured by using iodine as a starch indicator. A solution containing iodine and starch will have a dark blue color, whereas a solution containing iodine but no starch will have a light brown color. The color change of an iodine solution from dark blue to light brown can be used to measure the rate at which starch is converted to simple sugars. A student designs an experiment to investigate the effect of environmental pH on amylase function. The design of the experiment is presented in Table 1. Table 1. An experiment for investigating the effect of pH on amylase function Test Tube I II III IV V VI VII VIII Environmental pH 5 6 7 7 7 7 8 9 Starch Added Yes Yes No Yes Yes Yes Yes Yes Amylase Added Yes Yes Yes No Yes Yes Yes Yes Todine Added Yes Yes Yes Yes Yes Yes Yes Yes Pretreated by Boiling No No No No Yes No No No | Which of the following statements best justifies the inclusion of test tube V as a control in the experiment? (A) It will provide a measurement of amylase activity at an acidic pH. It will provide a measurement of amylase activity at a basic pH. It will show the color change that occurs in the absence of enzyme activity. It will show the color change that occurs in the absence of the amylase protein.

Answer 1

C) it will show the absence of color change in the absence of enze activity . Beacuse enzyme is present but it's activity is lost due to preheating , enzyme get denatured and become inactivated .

Option A) and B) are wrong beacuse amylase activity is lost , so how it will provide a measurement of amylase activity . Option c) is wrong beacuse amylase is present just it's activity is lost.