Enzymes functional in cells are called

Options

A. Endoenzymes
B. Exoenzymes
C. Apoenzymes
D. Isoenzymes.

Answer

**Step-by-Step Solution:**

1. **Understanding Enzymes**: Enzymes are biological catalysts that speed up biochemical reactions in living organisms. They can be classified based on their location and function.

2. **Identifying the Types of Enzymes**:
- **Endoenzymes**: These are enzymes that function inside the cell. They are also known as intracellular enzymes. They play a crucial role in various metabolic processes within the cell.
- **Exoenzymes**: In contrast, exoenzymes are enzymes that function outside the cell. They help in breaking down substances in the external environment.
- **Apoenzymes**: Apoenzymes refer to the inactive protein part of an enzyme. They require a cofactor to become active and catalyze reactions.
- **Isoenzymes**: Isoenzymes (or isozymes) are different forms of an enzyme that catalyze the same reaction but differ in their amino acid sequence.

3. **Determining the Correct Answer**: The question asks for enzymes that are functional in cells. Based on the definitions:
- Endoenzymes are the enzymes that function inside the cell, making them the correct answer.

4. **Conclusion**: Therefore, the correct answer to the question "Enzymes functional in cells are called" is **Endoenzymes**.

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