What is hibernation? What is its significance?

Explanation

### Step-by-Step Solution:

1. **Definition of Hibernation**:
Hibernation is commonly referred to as "winter sleep." It is a state of inactivity and metabolic depression in endotherms, primarily observed in certain animals like bears during the winter season.

2. **Purpose of Hibernation**:
The primary purpose of hibernation is to allow animals to survive adverse environmental conditions, particularly extreme cold. During this period, animals can conserve energy when food is scarce and temperatures are low.

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