RNA molecules having catalytic activity are called

Options

A. Ribozymes
B. Abzymes
C. Enzymes
D. All the above

Answer

To answer the question "RNA molecules having catalytic activity are called," we will analyze the options provided step by step.

### Step 1: Understand the Definition of Ribozyme
- Ribozyme is a type of RNA molecule that has the ability to catalyze biochemical reactions, similar to the way enzymes (which are typically proteins) do. This means that ribozymes can accelerate chemical reactions without being consumed in the process.

**Hint:** Remember that ribozymes are specifically RNA molecules with catalytic functions.

### Step 2: Evaluate the Options
- **Option A: Ribozyme**
- As discussed, ribozymes are RNA molecules with catalytic activity. This option is correct.

- **Option B: Abzymes**
- Abzymes are antibodies that have catalytic activity. They are not RNA molecules; instead, they are glycoproteins. Therefore, this option is incorrect.

- **Option C: Enzymes**
- Enzymes are primarily proteins that catalyze biochemical reactions. Like abzymes, they do not fall under the category of RNA molecules. Thus, this option is also incorrect.

- **Option D: All of the above**
- Since only ribozymes are RNA molecules with catalytic activity, this option is incorrect as well.

### Step 3: Conclusion
- Based on the analysis of the options, the only correct answer is **A: Ribozyme**. RNA molecules that exhibit catalytic activity are specifically referred to as ribozymes.

**Final Answer:** Ribozyme