Glycocalyx or cell coat which functions as the cell recognition center is made up of

Options

A. Proteins
B. Lipids
C. Proteins and lipids
D. Glycoproteins and glycolipids

Answer

### Step-by-Step Solution:

1. **Understanding Glycocalyx**: Glycocalyx, also known as the cell coat, is an outer layer found on the surface of the cell membrane. It plays a crucial role in cell recognition and communication.

2. **Composition of Glycocalyx**: The primary components of glycocalyx are polysaccharides. These are long chains of sugar molecules that contribute to the structure and function of the glycocalyx.

3. **Presence of Polypeptides**: In some microorganisms, such as Bacillus anthracis, the glycocalyx may also contain polypeptides. Polypeptides are made up of amino acids, and in this case, a specific amino acid known as D-glutamic acid is present.

4. **Formation of Glycoproteins**: When polysaccharides are combined with polypeptides, they form glycoproteins. Glycoproteins serve various functions, including cell recognition and signaling.

5. **Glycolipids**: Additionally, polysaccharides can also combine with lipid molecules to form glycolipids. Glycolipids consist of a carbohydrate attached to a lipid, and they also play a role in cell recognition.

6. **Conclusion**: Therefore, the glycocalyx or cell coat is primarily made up of glycoproteins and glycolipids, which are essential for cell recognition.

### Final Answer:
The glycocalyx or cell coat, which functions as the cell recognition center, is made up of glycoproteins and glycolipids.

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