which one is useful in metamprhosis of tadpole into frog.

Options

A. Oxytocin
B. Thyronxine
C. Pituitary hormone
D. Aldosterone

Answer

To answer the question "which one is useful in metamorphosis of tadpole into frog," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Metamorphosis**:
- Metamorphosis is the biological process through which an organism undergoes a significant change in form and structure from its juvenile stage to its adult stage. In this case, it refers to the transformation of a tadpole (the larval stage of a frog) into an adult frog.

2. **Identifying the Stages**:
- The life cycle of a frog includes several stages:
- Egg
- Tadpole
- Young frog
- Adult frog
- During metamorphosis, the tadpole undergoes various physiological changes to become a frog.

3. **Role of Hormones in Metamorphosis**:
- Hormones play a crucial role in regulating the metamorphosis process.
- The options given are oxytocin, thyroxin, pituitary hormone, and aldosterone.

4. **Identifying the Correct Hormone**:
- Among the options:
- **Oxytocin** is primarily involved in childbirth and lactation.
- **Aldosterone** is related to the regulation of sodium and potassium levels in the body.
- **Pituitary hormones** can influence growth and development but are not the primary hormones responsible for metamorphosis in frogs.
- **Thyroxin**, secreted by the thyroid gland, is known to regulate metabolism and is crucial for the metamorphosis of amphibians, including the transformation of tadpoles into frogs.

5. **Conclusion**:
- The hormone that is useful in the metamorphosis of tadpole into frog is **thyroxin**.

### Final Answer:
The correct answer is **thyroxin**.

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