Any substance (other than food) that is used to prevent, diagnose, treat, or relieve symptoms of a disease or abnormal condition. Drugs can also affect how the brain and the rest of the body work and cause changes in mood, awareness, thoughts, feelings, or behavior. Name an opioid drug and its source plant. How does the drug affect the human body?

Explanation

### Step-by-Step Text Solution:

1. **Identify an Opioid Drug**:
- One well-known opioid drug is **morphine**.

2. **Source Plant**:
- Morphine is derived from the **poppy plant**, specifically from the species known as **Papaver somniferum**.

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