Which cell is not present in connective tissue proper ?

Options

A. Erthrocytes
B. Lymphocytes
C. Plasma cell
D. Fibroblast

Answer

**Step-by-Step Solution:**

1. **Understanding Connective Tissue Proper**: Connective tissue proper includes various types of connective tissues such as loose connective tissue and dense connective tissue. It is characterized by the presence of a variety of cells and fibers embedded in a matrix.

2. **Identifying the Cells in Connective Tissue Proper**: The main cell types found in connective tissue proper include:
- **Fibroblasts**: These are the most common cells in connective tissue proper and are responsible for producing fibers and the extracellular matrix.
- **Plasma Cells**: These are derived from B lymphocytes and are responsible for producing antibodies.
- **Mast Cells**: These cells play a role in inflammatory responses and are involved in allergic reactions.
- **Lymphocytes**: These are a type of white blood cell that is part of the immune system.

3. **Identifying the Cell Not Present**: The question asks for a cell that is not part of connective tissue proper. Among the options provided:
- **Erythrocytes (Red Blood Cells)**: These cells are responsible for transporting oxygen and carbon dioxide in the blood. They are not a part of connective tissue proper.

4. **Conclusion**: Since erythrocytes are not found in connective tissue proper, the answer to the question is **erythrocytes**.

**Final Answer**: Erythrocytes (Red Blood Cells) are not present in connective tissue proper.

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