How do we detect the smell of an agarbatti (incense stick)?

Explanation

### Step-by-Step Solution:

1. **Understanding the Sense of Smell**: The process of detecting smells begins with our sense of smell, which is primarily facilitated by our olfactory system.

2. **Role of the Nose**: When we light an agarbatti (incense stick), it releases aromatic compounds into the air. These compounds travel through the air and enter our nose when we inhale.

3. **Olfactory Receptors**: Inside our nose, there are specialized sensory cells known as olfactory receptors. These receptors are responsible for detecting the chemical molecules present in the air, including those from the incense stick.

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