Ch 22 Taste Bud Anatomy/ Primary taste sensations/ Olfactory
Umami
Japanese word meaning 'delicious flavor'. 'Meaty' taste produced by amino acids in protein
Taste pore
a pit on the epithelial surface of the tongue that opens into a taste bud. Taste hairs project into the taste pore.
Bitter
associated with spoiled food and alkaloids such as nicotine, caffeine, quinine, and morphine. Alkaloids are usually poisonous and bitter taste cause us to reject a food
Supporting cells
lie between olfactory neurons and sustain the receptor cells
Olfactory receptor cells
neurons that detect odors only neurons directly exposed to the external environment lifespan of 60 days then replaced shaped like inverted bowling pins inferior, apical head has 10-20 immobile cilia- olfactory hairs - olfactory hairs have binding sites for odorant molecules basal end of cell tapers to become an axon axons travel through cribiform foramina to olfactory bulb
Gustatory (taste) cells
numerous banana-shaped cells with a tuft of microvilli (taste hairs) on apical surface, specialized neuroepithelial cells that synapse with sensory nerve fibers. Taste hairs serve as receptor surfaces for chemical molecules. live for 7 to 10 days
Salty
produced by metal ions such as sodium and potassium. When these levels fall, we crave salty foods
Sweet
produced by sugars and other organic molecules. Associated with carbohydrates and foods with high caloric content.
Facial nerve VII
receive signals from taste buds on anterior two-thirds of tongue
Glossopharynegal nerve (IX)
receives signals from taste buds on the posterior one third of the tongue
Name the 5 primary taste sensations
salty, sweet, sour, bitter, umami
Olfaction
sense of smell
Basal cell
stem cells that constantly divide and replace the dead gustatory cells. Replacement slows about the age of 50, and taste sensation begins to decline
Basal cells
stem cells to continually replace olfactory receptor cells
supporting cells
surround and resemble gustatory cells. have no sensory function
olfactory epithelium
two postage stamp-sized patches of epithelium that line the superior region of the each nasal cavity . Covers both superior nasal conchae, upper nasal septum, and the inferior surface of the cribiform plate of each nasal fossa. Composed of three cell types: olfactory receptor cells, supporting cells, basal cells
Sour
usually associated with acids (H+) in foods such as citrus fruits