Saqib performed the following steps in sequence as a part of an experiment.1) Added equal amounts of starch solution into two test tubes, I and II2) Added salivary amylase to test tube I and boiled amylase solution to test tube II3) Shook the test tubes and left them in a water bath for 10 minutes at 37°C4) Added a few drops of iodine solution to each test tubeHe observed that the contents of test tube I turned reddish yellow in color, and test tube II maintained its blue color.The CORRECT inference that he must have made based on his observations of test tube I and test tube II is
Correct answer: D. D
- A. A
- B. B
- C. C
- D. D
Explanation
In test tube 1, amylase hydrolyzed starch to small molecules of maltose, not fructose, giving a reddish-yellow color with iodine. In test tube 2, starch was not hydrolyzed because boiling inactivated amylase. Option D is correct. A, B, and C are incorrect, as they don't agree with the experimental results.
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About Factors Affecting Enzyme Action
Enzyme activity changes with temperature, pH, substrate concentration and enzyme concentration because these factors affect molecular collisions and the active site. Questions also examine optimum conditions, denaturation and inhibition, while distinguishing a fall in activity caused by unsuitable conditions from permanent enzyme damage.
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