Yixia Gu: Smell

How on earth do we smell? The process is simple but fascinating:

Suppose you opened the fridge one day and is overcome by a stinking sensation of moldy cheese. This particular smell is made up of special chemical cells (odorants) which when passing through our nostrils stimulate tiny cilia hairs which gather together in a small patch in the nose. In these hairs are contained special cells which receive the odours: Olfactory receptor cells. These cells are connected to the certain areas of the brain through a series of nerve pathways, and convert the detected smell as signals. Once the nerve signal reaches the brain, the brain processes these patterns so that we end up perceiving the signal as smell (in this case, the smell of moldy cheese).

Our sense of smell can add colour to our world, because what we sense through the olfactory receptors becomes perception. In addition smell also plays an active role in our emotions and memory depending what we associate each smell with.
Sources:
1) http://www.senseofsmell.org/feature/smell101/lesson1/01.php
2)http://www.blkbox.com/~rdevere/tsdc/howwork.html
3)http://health.howstuffworks.com/smell.htm