SEARCH
🇬🇧
MEM
O
RY
.COM
4.37.48
Guest
Log In
Â
Homepage
0
0
0
0
0
Create Course
Courses
Last Played
Dashboard
Notifications
Classrooms
Folders
Exams
Custom Exams
Help
Leaderboard
Shop
Awards
Forum
Friends
Subjects
Dark mode
User ID: 999999
Version: 4.37.48
www.memory.co.uk
You are in browse mode. You must login to use
MEM
O
RY
  Log in to start
Index
 »Â
L20 HNS
 »Â
Chapter 1
 »Â
Level 1
level: Level 1
Questions and Answers List
level questions: Level 1
Question
Answer
tasted by edges of the tongue ,. H+ions bind to K+channels, blocking them, and preventing K+from leaving the cell resulting in depolarization
Sour
tasted by anterior part of the dorsum of the tongue.NaCl in food activates epithelial Na channels (ENaC)which cause Na+influx
Salt
organic chemicals e.g. sugars, glycols, alcohols, aldehydes, ketones, and inorganic salts of lead and beryllium. It is tasted by the tip of the tongue bind with a plasma membrane receptor that activates a G-protein called "gustatin" cause production of cAMP. This leads to phosphorylation of K+channels decreasing K+leakage
Sweet
Long-chain organic substances that contain nitrogen, and Alkaloids tasted by the back of the tongue increase intracellular messenger inositol triphosphate (IP3) which causes the release of Ca2+
Bitter
in food containing L-glutamate such as meat extracts and aging cheese. It is tasted by all parts of the tongue activate mGluR4. These receptors allowNa+influx & K+ efflux
Umami
Taste binding protein that transports the tastant and concentrates it at taste buds.Then the tastant binds to its specific receptors in the microvilli of gutstatorycells causing potential changes in the taste receptor cell and release of the chemical transmitter. produced by
Ebner's
taste From anterior 2/3 of the tongue are carried by the
chorda tympani nerve (branch of the facial nerve).
From the posterior 1/3 of the tongue are carried by the
glossopharyngeal nerve
From the pharynx, hard and soft palate and epiglottis are carried by the
vagus nerve.
First order neurons of Gustatory Pathway
from the taste buds to the gustatory nucleus (nucleus solitarius)
Second order neurons of Gustatory Pathway
From the gustatory nucleus (nucleus solitarius) to ipsilateral medial lemniscus and pass directly to the (VPMNT)
complete loss of taste
ageusia
taste hallucinations
phantogeusia
yellow-brown pigments, tubular Bowman's glands& absence of rhythmic ciliary movements
Olfactory Mucosa
Olfactory Mucosa innervated by
Olfactory (cranial I) nerve& trigeminal
1storder neuron The Olfactory Pathways
Olfactory receptors pass through the cribriform plate to end in the glomeruli in the olfactory bulb.
2ndorder neurons in The Olfactory Pathways
mitral and tufted cells present in the olfactory bulbs that leaves the bulb to the olfactory cortex
inhibitory interneurons present in the bulb that produce GABA to inhibit mitral and tufted cells
Periglomerularcells & Granule cells
located anterior to the hypothalamus concerned with .Primitive responses to olfaction, such as licking the lips, salivation caused by the smell of food emotional associated with smell.
The medial olfactory area
area associated with Learning to like or dislike certain foods & Behavioral responses to food nausea and vomiting
Prepyriform and pyriform cortex + cortical portion of the amygdaloid nuclei
responsible for the conscious perception of olfaction i.e. analysis, interpretation and significance of the odour
the dorsomedial thalamic nucleusand that project to the orbitofrontal cortex
provides important olfactory information about odorants particularly pheromones, a substance that controls reproductive behaviourand
Vomero nasal organ