Winter sleep by frog is called

Options

A. aestivation
B. hibernation
C. amnesia
D. poikilotherms

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what the winter sleep of a frog is called. This refers to a specific physiological state that frogs enter during cold weather.

2. **Identifying the Options**: The options provided are:
- A) Estivation
- B) Hibernation
- C) Amnesia
- D) Polykleothems

3. **Analyzing Each Option**:
- **Estivation**: This term refers to a state of dormancy or inactivity that occurs in response to high temperatures or drought, not cold.
- **Hibernation**: This is the correct term for the winter sleep of cold-blooded animals, including frogs. During hibernation, these animals enter a state of reduced metabolic activity to survive cold temperatures.
- **Amnesia**: This term is unrelated to sleep or dormancy; it refers to a loss of memory.
- **Polykleothems**: This term does not relate to the context of sleep or dormancy in animals.

4. **Conclusion**: Based on the analysis, the correct answer is **Hibernation**. Frogs, being cold-blooded animals, enter hibernation during winter to survive the cold.

**Final Answer**: The winter sleep by a frog is called **Hibernation**.

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