A protein conjugated to carbohydrates is

Options

A. Lecithoprotein
B. Glycoprotein
C. lipoportein
D. Metalloprotein.

Answer

To solve the question "A protein conjugated to carbohydrates is", we need to analyze the options provided and understand the definitions related to proteins and their conjugation with carbohydrates.

### Step-by-Step Solution:

1. **Understanding the Options**:
- The options given are:
- a) Lecithoprotein
- b) Glycoprotein
- c) Lipoprotein
- d) Metalloprotein

2. **Identifying the Correct Term**:
- **Lecithoprotein**: This is a type of protein that is associated with lecithin (a phospholipid) but does not specifically refer to carbohydrate conjugation.
- **Glycoprotein**: This is a protein that has carbohydrates (oligosaccharides) covalently attached to it. This is the key term we are looking for.
- **Lipoprotein**: This refers to proteins that are conjugated with lipids, not carbohydrates.
- **Metalloprotein**: This refers to proteins that contain metal ions as part of their structure, not carbohydrates.

3. **Conclusion**:
- The correct answer is **b) Glycoprotein**. Glycoproteins are formed by the covalent linkage between oligosaccharides and polypeptide side chains through a process known as glycosylation.

4. **Additional Information**:
- Glycoproteins play important roles in cell-cell interactions and are produced in the endoplasmic reticulum and Golgi apparatus. The endoplasmic reticulum is responsible for producing N-linked sugars, while the Golgi apparatus produces O-linked sugars.

### Final Answer:
**A protein conjugated to carbohydrates is a Glycoprotein.**

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