Olfactory receptor neuron
Olfactory receptor neuron is a neuron found in vertebrates and insects.
The olfactory receptor neuron is located in the olfactory epithelium in the nose. It is a sensory neuron used to detect odors that are inhaled through the nostrils. The olfactory meurons are responsible for smell. It begins with the activation of the neurons in the epithelium from an odorant. Each neuron has one or a few receptors. These receptors are specific for a particular odorant. There are approximately 2,000 glomeruli that are on the outside of the olfactory bulb. The glomeruli gets imputs from the olfactory receptor neuron that comes from the nose.
The ORN is a bipolar neuron whose dendrite faces the nasal cavity and the axon goes towards the olfactory bulb. The dendrite has cilia that goes into the surface of the olfactory epithelium. Olfactory receptors are on the surface of the cilia and it is capable of binding one type of odor.
Neurotransmitter: Glutamate (Glutamic acid), most common in brain
Neuronal Type: Sensory neuron
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