taste + smell

Question 1

بسم الله الرحمن الرحيم
______________
Mention Sturcure of Taste receptors

Answer 1

Taste Buds
_________
formed of
Taste cells
Supporting cells
Basal cells stem cells

Question 2

Describe gustatory cells

Answer 2

Taste cells
MOdified epithelium
with apical microvilli
Stimulated by chemicals dissolved in saliva
turn over = 10 days

Question 3

Mention sites of taste buds

Answer 3

Palate + Pharynx + upper esophageal
Upper tongue
lateral tongue
V line connection of ant and post tongue

Question 4

Compare between Sugar and salt receptors
Site stimulus mechanism

Answer 4

Sugar :
Tip of tongue
Sugars: glucose fructose
Aldehyde
ahlocohl
Aminoacids
Mechanism :
Metabotropic :- stimulating adenylyl cyclase then cAMP then PK then Opeing Na closing K channels causing depolarization opeinig ca voltage gated channels relasing Neurotransmitters

Salt :
dorsum
Na inoized salts
Direct entering into Na channels causing same path of deplarization and firing

Question 5

Describe Sour channels

Answer 5

Edges of tongue
By acids containg H+
____________________
Enters through Na channels with Na blocking K channels causing ?
depolarization + firing

Question 6

Compare between Umami and bitter receptors

Answer 6

Umami :
scattered
by Food additives : Glutamte + MSG mono sodium glutamate + AAs

Bitter :
Back of tongue
Stimulated ? organic substances as ?
caffine - alkaline

both are metabotropic increasing IP3
Increasing Ca intra receptors
casuing Release of NTs

Question 7

Loss of taste called 1
2- less sensitivity
3- hypersenitvity ?
4- abnorma mixed?

Answer 7

1-Agusia
2-Hypoagusia
3-Hyperaguisa
4-Dysaguisa

Question 8

Olfaction = smell
Receptors:
………………….:
A surface area of 2.5 Cm
in the ……+…….. parts of the
nasal cavity.

Answer 8

Olfactory epithelium
________________
Superior + POST

Question 9

Describe sturcture of Olfactory receptors

Answer 9

sUPPORTING cell for mucus
Basal stem cells for Turnover=2months
Olfactory receptor cells :-
bipolar cells with a knob of 6-12 nerve fibers containig Odorant binding protein receptor

Question 10

odorant must be ?

Answer 10

Volatile
H20 and mucus solube

Question 11

Stimulation of Olfaction how ?

Answer 11

When dissolved Odorant Attached to OBP odorant biniding protein receptos formng complex stimulating adenyly cyclase then
cAMP -PK opeining Na ca K channels causing receptor poteintal but not enought
so Ca entered causing ?
Cl outflux directly ?
Binding calmodulin causing more Cl- outfluc
causing depolariztion of the receptor and formation of AP in the nerve reaching the olfactory bulb to compelete the pathway

Question 12

Olfaction adapation Mechanism explain ?

Answer 12

life saving@@ ^_^
________________
Na-Ca exchanger is the Chief !
Causing out flux of Ca
decreased Cl outflux by Ca and Clamodulin
preventing Action potenrial generation
returning to resting state
loss of smell =rapid adaption

Question 13

Anosmoa =
Parosomia=
hymposomua =

Answer 13

lost smell
Hallcuination of smell
Decreased smell sens..

Question 14

الحمدلله رب العالمين :)