Physiology

Question 1

taste and smell receptors are what kind of receptors?

Answer 1

chemoreceptors

Question 2

stimulation of taste and smell receptors induces what?

Answer 2

pleasurable or objectionale sensation

Question 3

define gustation

Answer 3

act of tasting

Question 4

sensory receptor cells of taste are arranged how?

Answer 4

mainly packaged in taste buds

Question 5

what are the sense orgas of taste?

Answer 5

taste buds

Question 6

taste buds consist of what?

Answer 6

sensory receptor cells and support cells

Question 7

what is the life span of a taste receptor cell?

Answer 7

10 days

Question 8

how are taste receptor cells replaced?

Answer 8

from basal cells within the taste buds

Question 9

majoruty of tastebuds sit where?

Answer 9

papillae in tongue

Question 10

what are the 4 type of papillae?

Answer 10

filliform

fungiform

vallate

foliate

Question 11

what kind of papillae does not contain taste buds?

Answer 11

filliform

Question 12

binding of tastant to receptor cells does what?

Answer 12

alters cell ionic channels producing depolarising receptor potential

Question 13

receptor potential in tasting initiates what?

Answer 13

APs in afferent nerve fibres which synapse with receptor cells

Question 14

what cranial nerves transfer info from tongue to brainstem?

Answer 14

ant 2/3rds- chorda tympani branch of facial

post 1/3rd- glossopharyngeal

Question 15

what are the five primary tastes?

Answer 15

salty- NaCl

sour- H⁺

sweet- glucose configuration

bitter- tastants i.e alkaloids

umani (meaty/savoury)- amino acids especially glutamate

Question 16

define ageusia

Answer 16

loss of taste

causes- nerve damage, inflamation, endocrine

Question 17

define hypogeusia

Answer 17

reduced taste function

causes: chemo, meds

Question 18

define dysgeusia

Answer 18

distortion of taste

casues- glossitis, gum infection, URTI, zic deficiency

Question 19

define olfaction

Answer 19

act of smelling

Question 20

what are the three cell types in olfactory mucosa?

Answer 20

olfactory receptor cells

supporting cells

basal cells

Question 21

describe the neurones of olfactory receptors

Answer 21

thick short dendrite and an expanded end called olfactory rod

Question 22

what is the life span of an olfactory receptor?

Answer 22

2 months

Question 23

axons of olfactory receptors colectively form what?

Answer 23

afferetn fibres of olfactory nerve

Question 24

what transmits smell information to the brain?

Answer 24

olfactory bulbs

Question 25

to be smelled a substance mus tbe what?

Answer 25

sufficiently volatile (can enter nose with inpsired air)

sufficiently water soluble (can dissolve in mucosa)

Question 26

define anosmia

Answer 26

inabilty to smell

causes- viral infection, allergy, nasal polyps

Question 27

define hyposmia

Answer 27

reduced ability to smell

causes- similar ot anosmia

n.b can be early indicator of parkinsons

Question 28

define dysosmia

Answer 28

altered sense of smell