gustation

Question 1

steps of taste perception

Answer 1

tongue > papillae> taste bud > receptor > depolarisation of taste cell > cascade of messages to the brain

Question 2

type of papillae

Answer 2

filiform
fungiform
circumvallate
foliate

Question 3

describe filiform papillae

Answer 3

upper surface/ middle line of tongue
- no taste buds
-gripping, textural perception (functional role)

Question 4

describe fungiform papillae

Answer 4

> 100 on each side
2-4 taste buds each

Question 5

describe foliate papillae

Answer 5

side of tongue, less of them
several hundred taste buds

Question 6

describe circumvallate papillae

Answer 6

makes a V shape on back of tongue
7 of them
several hundred tastes on each

Question 7

what is a taste bud

Answer 7

special sense organ located on tongue and soft palate contains receptors for tase

Question 8

what % of taste buds are on papillae

Answer 8

75%

Question 9

where are taste buds found

Answer 9

papillae and soft pallete

Question 10

when do taste buds develop

Answer 10

7-8 weeks gestation
structurally mature 13-15 weeks

Question 11

how does taste transduction occur (salt and sour)

Answer 11

complex chemical events
H+ (sour) and Na+ (salt) interact with ion channels
-increase within a cell which depolarizes the membrane and the Ca channel opens, causing release of neurotransmitter

Question 12

Taste transduction of sweet, umami, bitter

Answer 12

interact with membrane-bound protein (G-protein)
-membrane conductance changes resulting in transmission of the nerve signal at synaptic terminal through the release of neurotransmitters which stimulate the next cell in the sequence

Question 13

three taste nerves

Answer 13

chorda tympani nerve
glossopharyngeal nerve
vagus nerve

Question 14

most robust sense?

Answer 14

taste

Question 15

why might taste be so robust

Answer 15

three nerves innervate THE TONGUE

Question 16

components of a taste bud

Answer 16

taste pore
epithelial cells
taste cell
taste nerves

Question 17

what is adaptation

Answer 17

decrease in responsiveness under constant stimulus

Question 18

what is cross-adaptation

Answer 18

similar compounds having the same adaptation affect on each other

Question 19

example of cross adaptation

Answer 19

adaptation to NaCl will also decrease the perceived intensity of other salts

Question 20

what is mixture suppression

Answer 20

when a taste mixture shows a partially inhibitory/masking affect

Question 21

two types of mixture suppression

Answer 21

mutual
dominating

Question 22

what is mutual mixture suppression

Answer 22

both mixed compounds show a decline in sensitivity

Question 23

what is dominating mixture suppression

Answer 23

one taste dominates the other but is perceived as weaker

Question 24

example of dominating mixture suppression

Answer 24

quinine + sucrose is less bitter than quinine alone

Question 25

what is mixture interaction

Answer 25

Increased or decreased intensity perception based on previous components

Question 26

personal factors affecting taste

Answer 26

human variation age genetics

Question 27

explain the variation seen in human taste

Answer 27

everybody has different sensitivities for different compounds

Question 28

explain how age affects taste perception

Answer 28

taste cell replacement slows, having adverse effects on taste function

Question 29

example of how genetics effects taste perception

Answer 29

differences in bitter sensitivities to PROP is linked to a genetics

Question 30

what has PROP taster status been linked to

Answer 30

decreased consumption of leafy greens low caffeine and alcohol intakes increased capsaicin responsiveness overall decreased anti-oxidant status