Which one protects bacteria from enzymes present in the external medium ?

Options

A. Slime layer
B. S- layer
C. Flagella
D. Cell wall.

Answer

**Step-by-Step Solution:**

1. **Understanding the Structure of Bacteria**: Bacteria have a cell envelope that consists of various layers. This envelope is crucial for their survival and protection.

2. **Identifying the Protective Layer**: Among the various components of the bacterial cell envelope, the "S-layer" (surface layer) is significant. This layer is found in almost all archaea and many types of bacteria.

3. **Composition of the S-layer**: The S-layer is composed of a monomolecular layer made up of identical proteins or glycoproteins. This unique structure is essential for its protective function.

4. **Function of the S-layer**: The S-layer serves as a protective barrier for bacteria. It shields them from enzymes and other harmful substances present in the external environment. This protection is crucial for maintaining the integrity and structure of the bacterial cell.

5. **Conclusion**: Therefore, the S-layer is the component that protects bacteria from enzymes present in the external medium.

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