Salivery glands of cockroach open on :

Options

A. maxilla
B. hypopharynx
C. labium
D. labrum

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where the salivary glands of a cockroach open. This requires knowledge of the anatomy of the cockroach and the function of its salivary glands.

2. **Identifying the Options**: The options provided are:
- A) Maxilla
- B) Hypopharynx
- C) Labium
- D) Labrum

3. **Function of Salivary Glands**: Salivary glands in cockroaches are responsible for secreting saliva, which contains mucus that aids in lubrication during feeding.

4. **Analyzing Each Option**:
- **Maxilla**: These are mouthparts that help in manipulating food but do not serve as openings for salivary glands.
- **Hypopharynx**: This is a tongue-like structure in cockroaches through which the salivary glands release saliva.
- **Labium**: This is another mouthpart that acts like a lip but does not open for salivary secretion.
- **Labrum**: Similar to the labium, it is also a lip structure and does not function as an opening for salivary glands.

5. **Conclusion**: The salivary glands of the cockroach open on the hypopharynx, making option B the correct answer.

**Final Answer**: The salivary glands of the cockroach open on the hypopharynx (Option B).

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