Taste

Question 1

taste buds

Answer 1

1) filliform does not have tsate buds

Question 2

taste receptors

Answer 2

1 )primarily in the taste buds
2) greatest percentage in the upper surface of the tongue
3) gustatory epithelial cells
4) packaged with supporting cells
5) small portion exposed to surface of the tongue through taste pores
- allow fluid in the mouth to come into contact with receptors

Question 3

taste cell receptor

Answer 3

1) microvilli protrude slightly through the taste pore
2) receptors on the PM bind the chemicals
- specific binding
- chemicals in solution activate it
- ingested liquids or solids dissolved in saliva

Question 4

life spans of gustatory cells

Answer 4

1) most receptors are sheltered from direct exposure
2) life span 10 days
- basal epithelial cells => supporting cells => gustatory epithelial calls
3) bad burns will get rid of taste in that area
- recovery is quick

Question 5

general signal transduction

Answer 5

1) tastants (sapids)
- taste provoking chemical
2) taste discrimination coded by patterns of activity in various taste bud receptors
3) five primary tastes
- sours, salty, sweet, bitter, umami
4) tastant => taste receptor => signal cascade => depolarization => voltage gates Ca2+ channel => release NT

Question 6

salty taste

Answer 6

1) principal stimulus is Na+
- other cations (ammonium, lithium, potassium)
2) anions contribute to taste intensity
- saltiness NaCl > Na2SO4
3) receptor mechanisms is incompletely understood

Question 7

sour taste

Answer 7

1) sour taste with acids
2) acidophore
- functional group of sour compounds
3) organic acids
- undissociated or partially dissociated acid molecules
4) loose correlation with pH
- lower pH is sour
- exception, HCl is relatively tasteless

Question 8

umami

Answer 8

1) savory or meaty
2) monosodium glutamate
3) meat, cheeses, tomatoes, mother’s milk

Question 9

sweet taste

Answer 9

1) prototype = sucrose
- other sugars: monosaccharides, some oligosaccharides (glycose, partially hydrolyzed starch)
2) amino acids
- glycine, alanine, etc
3) peptides and proteins: aspartame
4) alcohols: glycerol, sorbitol, xylitol
5) other synthetic compounds
- artificial sweeteners
6) dilute solutions of simple ions
- NaCl, LiCl, lead

Question 10

bitter

Answer 10

1) most diverse
- denatonium benzoate (most bitter)
2) generally adverse taste

Question 11

gustatory pathway

Answer 11

1) terminal afferent endings of cranial nerves terminate on taste buds in the mouth
- signals are conveyed to gustatory cortex
2) taste also sent to the hypothalamus and limbic system to affect affective dimensions
- weather the taste is pleasant or unpleasant
- to process behavioral aspect associates with taste and smell