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Olfactory Synthesis

Satisfactory Essays
Olfaction, also known as sense of smell, is the detection and recognition of chemicals that contact membranes inside the nose. Substances that we can smell in the air, or small airborne molecules, are called odorants. Odorants bind to olfactory receptor proteins (G-protein-coupled receptors) in the cilia of the olfactory sensory neuron to employ a second-messenger system to respond to the presence of odorants. The sense of smell begins with receptor neurons in the nose. The olfactory epithelium is responsible for detecting odors and has three types of cells: olfactory sensory neurons (OSN), basal cells and supporting cells. Odorants depolarize olfactory receptor cells (or OSN) through axons that travel through the cribriform plate—a bony barrier between the nose and brain. The olfactory sensory neurons axons send…show more content…
Each glomerulus within the olfactory bulb is a tight little sphere of neural circuitry that receives inputs exclusively from olfactory neurons that are expressing the same type of olfactory receptor. Olfactory information is conveyed to the brain via the axons of mitral cells, which extend from the glomeruli in the olfactory bulbs to various regions of the forebrain. Important targets for olfactory inputs include the hypothalamus, the amygdala, and the prepyriform cortex (primary olfactory cortex). The overall pattern of activity in the olfactory bulb and cortex determines the odor we perceive. There are two types of olfaction: orthonasal and retronasal. Orthonasal olfaction involves odorants being inhaled through the nose. Retronasal is the process in which humans smell through the throat and nose. Odorants are forced up behind the palate, or expired, then diffused through the nasopharynx to the olfactory receptors. This occurs when the odorants travel up the throat and into the nasal cavity. It is important for food selection and therefore linked to
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