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Read the following statements about enzy...

Read the following statements about enzymes.
Which among them are correct?
I. The mechanism by which enzymes work is known as lock and key.
II. They denature at high temperatures.
III. They are mostly proteins having a tertiary structure.
IV. They may be assisted by vitamins and minerals.

A

I , II and III only

B

I , II , III and IV

C

II and IV only

D

I , II and IV only

Text Solution

AI Generated Solution

The correct Answer is:
To determine which statements about enzymes are correct, let's analyze each statement one by one: ### Step 1: Analyze Statement I **Statement I:** The mechanism by which enzymes work is known as lock and key. - **Explanation:** The lock and key model describes how enzymes and substrates fit together perfectly, similar to a key fitting into a lock. This model emphasizes the specificity of enzymes for their substrates. - **Conclusion:** This statement is **correct**. ### Step 2: Analyze Statement II **Statement II:** They denature at high temperatures. - **Explanation:** Denaturation refers to the process where the structure of an enzyme is altered, usually due to extreme conditions such as high temperature. High temperatures can disrupt the bonds that maintain the enzyme's structure, leading to loss of function. - **Conclusion:** This statement is **correct**. ### Step 3: Analyze Statement III **Statement III:** They are mostly proteins having a tertiary structure. - **Explanation:** Enzymes are indeed primarily proteins, and they typically have a complex three-dimensional shape known as tertiary structure. This structure is crucial for their catalytic activity. - **Conclusion:** This statement is **correct**. ### Step 4: Analyze Statement IV **Statement IV:** They may be assisted by vitamins and minerals. - **Explanation:** Many enzymes require additional non-protein molecules called cofactors to function properly. These cofactors can include metal ions (like zinc and magnesium) and organic molecules (like vitamins). - **Conclusion:** This statement is **correct**. ### Final Conclusion All four statements about enzymes are correct. Therefore, the correct answer is: - **I, II, III, and IV are all correct.** ---
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