The olfactory nerve in zebrafish is composed of olfactory sensory neuron (OSNs) axons. There are three types of olfactory sensory neuron in fish, cilliated cells,microvillus sensory neruons and crypt cells (Kermen et al., 2013). Chemical odorants in the water are detected by olfactory receptors on the OSNs who have their soma located inside the olfactory epithelium(the zebrafish nose). OSN axons innervate the olfactory bulb where they connect with the dendrites of mitral cells and other olfactory bulb neurons at structures called glomeruli.
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Neural circuits mediating olfactory-driven behavior in fish
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