Why does asthma cause breathlessness?

Explanation

### Step-by-Step Solution:

1. **Understanding Normal Breathing**:
- In normal circumstances, breathing involves inhaling oxygen through the nose, which travels down the trachea (windpipe) and into the bronchioles, ultimately reaching the lungs. When exhaling, the process reverses, allowing carbon dioxide to exit the body through the same pathways.

2. **Identifying the Problem in Asthma**:
- In individuals with asthma, the respiratory tract experiences swelling. This swelling occurs in the airways that facilitate breathing.

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