Define. Hibernation

Answer

**Step-by-Step Text Solution:**

1. **Understanding Hibernation:**
- Hibernation is a physiological state that some animals enter to survive adverse environmental conditions, particularly during winter.

2. **Metabolic Activity:**
- During hibernation, the animal's metabolic activities significantly decrease. This includes a reduction in body temperature, heart rate, and breathing rate.

3. **Seasonal Heterothermy:**
- Hibernation is often referred to as seasonal heterothermy, which means that the animal's body temperature and metabolic rate fluctuate with the seasons.

4. **Timing:**
- Hibernation typically occurs during the winter season when food is scarce and temperatures are low.

5. **Conclusion:**
- In summary, hibernation is a survival strategy that allows animals to conserve energy by drastically lowering their metabolic functions during unfavorable conditions.

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