The first enzymes were

Options

A. Proteinaceous
B. RNA molecules
C. Inorganic
D. Lipids

Answer

To answer the question "The first enzymes were," we will analyze the options provided and derive the correct answer based on the information about the origin of life and the nature of enzymes.

### Step-by-Step Solution:

1. **Understanding the Origin of Life**:
- The origin of life on Earth is believed to have occurred in a reducing atmosphere, which consisted of gases like methane, ammonia, hydrogen, and water vapor. This environment facilitated the formation of simple organic molecules.

2. **Miller-Urey Experiment**:
- The Miller-Urey experiment simulated the conditions of early Earth and demonstrated that organic compounds, specifically amino acids, could be synthesized from inorganic precursors. This experiment is crucial in understanding how life may have originated.

3. **Formation of Biological Molecules**:
- Following the formation of amino acids, these molecules can link together to form peptides and eventually proteins. Proteins are essential biological molecules that play a critical role in various cellular functions.

4. **Nature of Enzymes**:
- Enzymes are biological catalysts that speed up chemical reactions in living organisms. They are primarily composed of proteins. Therefore, the first enzymes that emerged in early life forms would have been proteinaceous.

5. **Evaluating the Options**:
- Now, let's evaluate the options given:
- **Proteinaceous**: This option is consistent with the understanding that enzymes are proteins.
- **RNA molecule**: While RNA can have catalytic properties (ribozymes), the question specifically asks for enzymes, which are typically proteins.
- **Inorganic**: Enzymes are organic molecules, so this option is incorrect.
- **Lipids**: While lipids are important for cellular structures, they are not enzymes.

6. **Conclusion**:
- Based on the information and analysis, the correct answer is that the first enzymes were **proteinaceous**.

### Final Answer:
The first enzymes were **proteinaceous**.