How do we detect the smell of an agarbatti (incense stick)?
The smell of an agarbatti (incense stick) is detected by the olfactory receptors present in our nose. These receptors are the specialised tips of some nerve cells located in our sense organs.
All information from our environment is detected by these specialised tips of nerve cells. The olfactory receptors, situated in the nose, specifically detect smell. When the fragrance from the agarbatti reaches our nose, these receptors receive the information and transmit it for further processing.
Explanation
The textbook clearly states that olfactory receptors detect smell and that these receptors are the specialised tips of nerve cells located in sense organs like the nose. The answer follows the sequence: identifying the receptor type (olfactory), its location (nose), and explaining that it is a specialised tip of a nerve cell that detects environmental information.