Select incorrect statement regarding cell envelope in prokaryotes.

Options

A. Most prokaryotic cells have a chemically complex cell envelope.
B. Each layer of the envelope performs same function
C. It has outermost glycocalyx followed by the cell wall and then the plasma membrane.
D. The cell envelope consists of a tightly bound there layered structure

Answer

To solve the question regarding the incorrect statement about the cell envelope in prokaryotes, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Cell Envelope Structure**:
- The cell envelope in prokaryotes typically consists of a plasma membrane and a cell wall. Some prokaryotes also have an outer layer called the glycocalyx.

2. **Analyze Each Statement**:
- **Statement 1**: "Most prokaryotic cells have a chemically complex cell envelope."
- This statement is correct. Prokaryotic cell envelopes can be complex, especially in bacteria with additional layers.

- **Statement 2**: "Each layer of the envelope performs the same function."
- This statement is incorrect. The plasma membrane and cell wall have different functions; the plasma membrane regulates the entry and exit of substances, while the cell wall provides structural support.

- **Statement 3**: "It has outermost glycocalyx followed by the cell wall and then the plasma membrane."
- This statement is correct. In many prokaryotes, the glycocalyx is indeed the outermost layer, followed by the cell wall and then the plasma membrane.

- **Statement 4**: "The cell envelope consists of a tightly bound, three-layered structure."
- This statement is also correct. The cell envelope can be described as a three-layered structure in many prokaryotes, consisting of the glycocalyx, cell wall, and plasma membrane.

3. **Identify the Incorrect Statement**:
- After analyzing all the statements, it is clear that **Statement 2** is the incorrect one regarding the cell envelope in prokaryotes.

### Final Answer:
The incorrect statement regarding the cell envelope in prokaryotes is **Statement 2**: "Each layer of the envelope performs the same function."

---