Endostyle of Amphioxus is similar to :

Options

A. Parathyroid
B. Thymus
C. Thyroid
D. Thalamus

Answer

**Step-by-Step Solution:**

1. **Understanding the Endostyle**: The endostyle is a pharyngeal organ found in Amphioxus, which is known for its role in iodine metabolism and concentrating iodine.

2. **Analyzing the Options**:
- **Option A: Parathyroid**: The parathyroid glands are responsible for regulating calcium levels in the blood by releasing parathyroid hormone. This function is not related to iodine metabolism, making this option incorrect.

- **Option B: Thymus**: The thymus gland is involved in the immune system, particularly in the maturation of T-cells, through the secretion of the hormone thymosine. This function does not relate to iodine, so this option is also incorrect.

- **Option C: Thyroid**: The thyroid gland plays a crucial role in metabolism and growth by releasing hormones such as thyroxine, which contains iodine. The endostyle of Amphioxus is homologous to the thyroid gland because both are involved in iodine metabolism. This makes this option correct.

- **Option D: Thalamus**: The thalamus is a part of the brain that relays sensory and motor signals to the cerebral cortex. It does not have any relation to iodine or metabolism, making this option incorrect.

3. **Conclusion**: After analyzing all the options, the endostyle of Amphioxus is similar to the thyroid gland due to its iodine metabolism functions.

**Final Answer**: The endostyle of Amphioxus is similar to the Thyroid gland.

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