Enzymes are regarded as

Options

A. biocatalysts
B. activators
C. messengers
D. antibodies

Answer

### Step-by-Step Solution:

1. **Definition of Enzymes**: Enzymes are biological molecules that act as catalysts in biochemical reactions. They are primarily composed of proteins and have a specific three-dimensional structure that is crucial for their function.

2. **Function of Enzymes**: The main role of enzymes is to accelerate biochemical reactions. They do this by lowering the activation energy required for the reaction to occur, which allows the reaction to proceed more quickly.

3. **Biocatalysts**: Because enzymes facilitate biological reactions, they are often referred to as biocatalysts. This term highlights their role in speeding up reactions that are essential for life processes.

4. **Incorrect Options**:
- The second option mentioned in the transcript refers to "Activator," which is not the same as an enzyme. Activators are molecules that increase the activity of enzymes but are not enzymes themselves.
- The third option mentions "Messengers," which typically refers to molecules that transmit signals in the body, such as hormones or neurotransmitters. This is also not related to the function of enzymes.

5. **Conclusion**: Based on the information provided, the correct characterization of enzymes is that they are biocatalysts that facilitate biochemical reactions by lowering activation energy.

### Final Answer:
Enzymes are regarded as **biocatalysts** that speed up biochemical reactions by lowering activation energy.

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