There are several types of chemoreceptors throughout the body that detect chemicals, including taste buds, olfactory receptors, cutaneous nociceptors, muscle sensors, and circulatory sensors. Taste is detected by taste buds on the tongue, palate, and epiglottis that are innervated by cranial nerves, while smell is detected by olfactory receptors in the nasal cavity. Both taste and smell are mediated by chemoreceptors and involve the detection of water-soluble chemicals, but taste receptors are localized to specific areas of the tongue and there are fewer olfactory receptors than taste buds.

1. Dr. Mohanad R. Alwan

3. Taste and smell (chemical receptors) tend to influence each other Taste (gustation) Taste buds- epithelial cells that act like neurotransmitters Innervated by cranial nerves

6. Four major sensations of taste Sweet- G-protein activates second messenger system Bitter- also G-protein activated specific receptor Sour- proton channel (acids taste sour) Salty- sodium channels Tastes seem to be enhanced in different parts of the tongue

16. receptor cells in olfactory epithelium sense of smell transmitted directly to cerebral cortex (all others go through thalamus) receptors in medial temporal lobes and in limbic system (emotional response to odors) Molecular basis for smell is complex- humans can distinguish up to 10,000 different odors Smell (olfaction)

20. VOMERONASAL SYSTEM

29. The End