In insects, pheromone is secreted by

Options

A. Corpus callosum
B. Corpus luteum
C. Corpus albicans
D. Corpus allata.

Answer

To answer the question "In insects, pheromone is secreted by," we will analyze the provided options step by step.

### Step 1: Understand the term "pheromone"
- Pheromones are chemical substances produced and released into the environment by insects, which affect the behavior or physiology of others of the same species.

### Step 2: Evaluate the options
- **Option A: Corpus Callosum**
- The corpus callosum is a band of nerve fibers that connects the left and right hemispheres of the brain. It is not involved in pheromone secretion.
- **Conclusion**: Incorrect.

- **Option B: Corpus Luteum**
- The corpus luteum is a temporary endocrine structure involved in the menstrual cycle and pregnancy in higher animals. It secretes hormones like progesterone but is not related to pheromone production in insects.
- **Conclusion**: Incorrect.

- **Option C: Corpus Albicans**
- The corpus albicans is the degenerated form of the corpus luteum and does not secrete any hormones, including pheromones.
- **Conclusion**: Incorrect.

- **Option D: Corpus Alata**
- The corpus alata is a structure found in insects that is responsible for the secretion of juvenile hormones. These hormones play a crucial role in the development and metamorphosis of insects and are also involved in the production of pheromones.
- **Conclusion**: Correct.

### Final Answer
The correct answer is **D: Corpus Alata**. This structure is responsible for secreting pheromones in insects.

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