What are adaptations? Give their significance.

Explanation

### Step-by-Step Solution:

1. **Definition of Adaptations**:
Adaptations are the changes that organisms undergo to adjust to their environment. These changes can be classified into three main categories: morphological, physiological, and behavioral adaptations.

2. **Types of Adaptations**:
- **Morphological Adaptations**: These are physical changes in the structure of an organism. For example, the thick fur of polar bears helps them survive in cold climates.
- **Physiological Adaptations**: These involve internal body processes that help organisms survive. For instance, some desert plants have adapted to conserve water through specialized mechanisms.
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