Which of the following statements about enzymes is INCORRECT? MCQ with Answer and Explanation

Which of the following statements about enzymes is INCORRECT?
A. Enzymes are highly specific in action
B. Enzymes lower the activation energy of a reaction
C. Enzymes work optimally at high temperatures (>100°C)
D. Enzymes are proteins
Answer: Option C
Solution (By JKSSB Mock Tests)
Enzymes are biological catalysts that function optimally at moderate temperatures (around 35-40°C for human enzymes). Most enzymes denature and lose activity at temperatures above 50-60°C, as the protein structure unfolds. They are highly specific (lock-and-key model), protein in nature, and lower activation energy without being consumed. Some thermophilic bacteria have enzymes active at high temperatures, but typical enzymes are not stable at >100°C.

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The chemical name of Vitamin C is:
A. Retinol
B. Calciferol
C. Tocopherol
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Correct Answer: Option D


Explanation:
Vitamin C is chemically known as ascorbic acid (C6H8O6). It is a vital nutrient involved in the repair of tissue and the enzymatic production of certain neurotransmitters. Deficiency leads to scurvy. Retinol is Vitamin A, Calciferol is Vitamin D, and Tocopherol is Vitamin E.

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Pepsin is an enzyme that digests:
A. Proteins
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Correct Answer: Option A


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Pepsin, secreted in the stomach, breaks down proteins into peptides. It works in acidic pH. Amylase digests starch; lipase digests fats.

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Calgon is used for water softening. Its chemical name is:
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B. Sodium silicate
C. Sodium zeolite
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Correct Answer: Option D


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