Taste (1) Flashcards
What are the chemical senses?
Taste and smell
Another word for taste
Gustation
Another word for smell
Olfaction
What are the 4 types of papillae?
Filiform, fungiform, foliate, and circumvallate
Where is the fungiform papillae?
Scattered over the entire tongue surface (2/3 anterior), and only have 5 taste buds each
Where is the foliate papillae?
Laterally on the tongue, contain many taste buds during childhood but fewer with age
Where is the circumvallate?
Back of the tongue (1/3), form a V shape, and are the largest and least numerous papillae but have many taste buds (7-15)
What are gustatory (epithelial) cells?
Receptor cells for taste (taste cells)
What are gustatory hairs?
Long microvilli that project from the tips of all gustatory epithelial cells and extend through a taste pore to the surface of the epithelium, where they are bathed in saliva
They are also receptor membranes of the gustatory epithelial cells
What are taste pores?
Any of the small openings in the tongue epithelium that allow dissolved food to come into contact with the taste receptors
What are basal cells?
Act as stem cells and divide and differentiate into new gustatory epithelial cells every 7-10 days
What are the 5 basic tastes?
Sweet, sour, salty, bitter and umami
Sweet:
Sugars, alcohol and amino acids
Sour:
Acids, H+
Salty:
Inorganic salts, NaCl (cation and anion together)
Bitter:
Bases, nicotine and caffeine
Umami:
“delicious”, glutamate
What are the maps of sensory areas?
Taste buds can receive all tastes
The physiological need of the body an effect…
Psychological behavior
Chemical needs to be in a….
Solution
Solution for taste:
Saliva
What is transduction?
Changing the energy into something else.
Some things do things slightly different
Ex: change chemical to electrical impulse
What is gustducin?
Bitter, sweet and umami responses share a common mechanism, but each receptors is coupled to a common G protein (gustducin)
Activation leads to the release of Ca2+ from intracellular stores, which causes cation channels in the plasma membrane to open, thereby depolarizing the cell and releasing the neurotransmitter ATP
Taste is ____% smell
80%
Facial nerve (VII) transmits impulses from…
taste receptors in the anterior 2/3 of tongue
The lingual branch of the glossopharyngeal nerve (IX) services the….
posterior 1/3 of of the tongue and the pharynx just behind
The vagus nerve (X) primarily conducts…
taste impulses from the few taste buds in the epiglottis and the lower pharynx
What are the influences of smell?
Thermoreceptors, mechanoreceptors and nociceptors
Thermoreceptors:
Temp can change taste
Ex: cold pizza is better than hot pizza
Mechanoreceptors:
Ex: blending up food
Nociceptors:
Ex: hot foods such as peppers bring pleasurable effects by exciting pain receptors in the mouth
What are the first order neurons?
Cranial nerves- facial, glossopharyngeal and vagus
Glutamate is….
Savory
