“All enzymes are not proteins.” This statement is justified by:
**Core Concept**
Enzymes are biological molecules, typically proteins, that catalyze specific chemical reactions in living organisms. However, not all enzymes are proteins; some are ribonucleic acid (RNA) molecules known as ribozymes.
**Why the Correct Answer is Right**
This statement is justified by the existence of ribozymes, which are RNA molecules that possess catalytic activity. Ribozymes can catalyze specific chemical reactions, similar to protein enzymes. The mechanism of action of ribozymes involves the formation of a complex between the RNA molecule and the substrate, leading to the catalysis of the reaction. This is in contrast to protein enzymes, which rely on amino acid residues to participate in catalysis.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify the type of enzyme that is not a protein.
**Option B:** This option is incorrect because it implies that all enzymes are proteins, which contradicts the statement.
**Option C:** This option is incorrect because it does not provide any evidence to support the statement.
**Clinical Pearl / High-Yield Fact**
It is essential to remember that enzymes can be either proteins or RNA molecules, and understanding the difference between these two types is crucial for appreciating the diversity of biological catalysts.
**Correct Answer: C. This statement is a generalization that is not always true.**