Question

Three of the following statements about enzymes are correct and one is wrong. Which one is wrong?

• A. Enzymes are highly specific
• B. Enzymes require optimum pH for maximal activity
• C. Enzymes are denatured at high temperature but in certain exceptional organisms they are effective even at temperatures 80°-90°C
• D. Most enzymes are proteins but some are lipids

Answer 1

The correct option is D

Most enzymes are proteins but some are lipids

The correct option is D.

Explanation of the correct option:

Option D:

1. Enzymes are biological catalysts.
2. It can catalyze different biological reactions within a narrow range of temperature and pH.
3. At optimum temperature and pH, it shows maximum activity.
4. The specific enzyme has specific functions.
5. In high temperatures, most enzymes are denatured, but certain thermophiles have enzymes that remain functional even at very high temperatures.
6. Most enzymes are proteins but some are RNA enzymes e.g., ribozymes.
7. Ribozymes provide resistance to some viruses which are being applied in biotechnology in producing cDNA.

Explanations of the incorrect options:

Option A:

1. Enzymes are highly specific biocatalysts that only regulate a particular ligand in a specific reaction.
2. This is an incorrect option as the given option is true.

Option B:

1. This is an incorrect option as enzymes function maximally at a specific optimum range of pH.
2. This is a true statement.
3. Hence, it is an incorrect option.

Option C:

1. Enzymes work at a specific range of temperature and get easily denatured upon raising the temperature.
2. This is a true statement.
3. Hence, it is an incorrect option.

Final answer: So, 'most enzymes are proteins but some are lipids' this statement is wrong.