Define disease symptoms.

Explanation

### Step-by-Step Text Solution

1. **Understanding the Concept of Disease Symptoms**:
- Disease symptoms refer to the observable signs and changes in the body that indicate a disease is present. These symptoms can manifest as physical or functional alterations in the body's organs.

2. **Structural and Functional Changes**:
- Symptoms arise from structural (anatomical) and functional (physiological) changes in the body. For example, inflammation, swelling, or changes in organ function can all be classified as symptoms.

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