Editing Sensory neuron (section)

==== Smell ====
The sensory neurons involved in [[olfaction|smell]] are called [[olfactory receptor neuron|olfactory sensory neuron]]s. These neurons contain [[Receptor (biochemistry)|receptor]]s, called [[olfactory receptor]]s, that are activated by [[odor]] molecules in the air. The molecules in the air are detected by enlarged [[cilia]] and [[microvilli]].<ref>Breed, Michael D., and Moore, Janice. [https://books.google.com/books?id=O5lnDwAAQBAJ&q=%22sensory+neuron%22 Encyclopedia of Animal Behavior] . London: Elsevier, 2010. Print.</ref> These sensory neurons produce action potentials. Their axons form the [[olfactory nerve]], and they synapse directly onto neurons in the cerebral cortex ([[olfactory bulb]]). They do not use the same route as other sensory systems, bypassing the brain stem and the thalamus. The neurons in the olfactory bulb that receive direct sensory nerve input, have connections to other parts of the olfactory system and many parts of the [[limbic system]]. 9.