in which part of cockroach is present completely developed endoskeleton and exoskeleton both ?

Options

A. In head region
B. Thoracic region
C. Abdominal region
D. In all regions

Answer

To answer the question regarding the part of the cockroach where both a completely developed endoskeleton and exoskeleton are present, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Cockroach Anatomy**:
- The cockroach has a segmented body divided into three main regions: the head, thorax, and abdomen. Each of these regions has different structures and functions.

2. **Identifying the Endoskeleton and Exoskeleton**:
- The **exoskeleton** is the hard outer structure that provides protection and support, made primarily of chitin.
- The **endoskeleton** is an internal support structure that provides additional support and is less common in arthropods like cockroaches.

3. **Focusing on the Head Region**:
- The head of the cockroach is unique because it contains both an endoskeleton and an exoskeleton.
- The endoskeleton in the head is formed by a structure known as the **tentorium**, which is a supportive framework that helps in muscle attachment and provides structural integrity.

4. **Presence of Exoskeleton in the Head**:
- The exoskeleton in the head region consists of various hardened plates and structures, known as **apodemes**, which serve as points of muscle attachment.

5. **Conclusion**:
- After analyzing the regions, it is clear that the head region of the cockroach is the only area where both a completely developed endoskeleton (tentorium) and exoskeleton (apodeme) are present.

### Final Answer:
The part of the cockroach where both a completely developed endoskeleton and exoskeleton are present is the **head region**.

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