How the olfactory system makes sense of scents


The human nose is often considered something of a luxury, but in the rest of the animal world, from bacteria to mammals, detecting chemicals in the environment has been critical to the successful organism. An indication of the importance of olfactory systems is the significant proportion — as much as 4% — of the genomes of many higher eukaryotes that is devoted to encoding the proteins of smell. Growing interest in the detection of diverse compounds at single-molecule levels has made the olfactory system an important system for biological modelling.

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Figure 1: Functional anatomy and structure of the early olfactory system.
Figure 2: Odorant receptors are the jewel of olfactory research in the past 10 years.
Figure 3: Sensory transduction.


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Material for figures was provided by X. Zhang and A. Kini. Thoughtful comments were provided by members of my laboratory and D. Kelley.

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Correspondence to Stuart Firestein.

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Firestein, S. How the olfactory system makes sense of scents. Nature 413, 211–218 (2001).

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