In cockroach, larval and nymphal characters are maintained by

Options

A. Ecdysone
B. Salivary glands
C. Parotid glands
D. Juvenile hormone

Answer

To solve the question "In cockroach, larval and nymphal characters are maintained by," we will analyze the options provided and determine which one is correct based on biological understanding.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the maintenance of larval and nymphal characters in cockroaches. This involves understanding the developmental stages of cockroaches and the hormones that regulate these stages.

2. **Reviewing the Options**:
- **Achidzone**: This is an inactive form of a molting hormone but does not play a role in maintaining larval or nymphal characteristics.
- **Salivary Glands**: These glands are responsible for secreting saliva for digestion but do not influence the maintenance of larval or nymphal traits.
- **Parotid Glands**: These are major salivary glands found in higher animals, not in cockroaches, and are unrelated to the maintenance of larval or nymphal characters.
- **Juvenile Hormone**: This hormone is crucial in insects, including cockroaches, as it helps maintain juvenile characteristics during the molting process.

3. **Identifying the Correct Answer**: The juvenile hormone is secreted by the corpora allata and is responsible for retaining juvenile traits during the molting process. Therefore, it is the correct answer.

4. **Conclusion**: The correct option is **Juvenile Hormone**.

### Final Answer:
In cockroach, larval and nymphal characters are maintained by **Juvenile Hormone**.

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