Which type of structure in cockroach monitoring the environmental conditions-

Answer

**Step-by-Step Solution:**

1. **Identify the Structure**: The question asks about a structure in the cockroach that monitors environmental conditions. The relevant structure is the antennae.

2. **Understand the Anatomy**: The head of the cockroach is unsegmented and features a pair of compound eyes and a pair of antennae. The antennae are sensory appendages that arise from a membranous socket located on either side of the head.

3. **Types of Antennae**: The antennae are divided into three parts:
- A large basal scape
- A small pedicel
- A long filamentous jointed flagellum

4. **Function of Antennae**: The antennae are equipped with small sensory bristles that allow the cockroach to detect changes in its environment, such as humidity, temperature, and chemical signals.

5. **Conclusion**: Therefore, the structure responsible for monitoring environmental conditions in a cockroach is the antennae.

**Final Answer**: The antennae.

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