topic.7.the.senses.powerpoint.7.3.-taste.smell Flashcards
___responds to the presence of specific molecules in the environment
chemoreceptors
chemoreceptors in vertebrates can form parts of receptor organs for __ and __
taste(gustation), smell(olfaction)
papillae
specialized regions on the tongue
what is the acronym to remember the different types of papillae?
Freaky Vampires Feast Frequently
Filiform.
Vallate
Fungiform
Foliate
Filiform.
Filament-shaped; provide a rough surface for food manipulation
Vallate
Largest, least numerous. 8-12 in V along border between anterior
and posterior parts of the tongue. Have taste buds
Fungiform.
Mushroom-shaped. Scattered irregularly over the superior surface of tongue. Look like small red dots interspersed among the filiform.Have taste buds
Foliate.
Leaf-shaped. In folds on the sides of the tongue. Contain most
sensitive taste buds. Decrease in number with age.
Taste bud:
contain sensory receptor cells specific for each of the five taste types:
sweet, salty, bitter, sour,unami
How do taste buds detect taste?
Taste cells have microvilli (gustatory hairs)
extending into taste pores
What do we call food particles that have been in our mouth
“tastants”, which are dissolved in
saliva, enter the taste pores
*tastants cause the taste cells to depolarize
Sour.
Most sensitive receptors on lateral aspects of the tongue. H+ ion of acids cause depolarization
Salty.
Most sensitive receptors on tip of tongue. Shares lowest sensitivity with sweet. Anything with Na+ causes depolarization
Bitter.
Most sensitive receptors on posterior aspect. Highest sensitivity. Sensation produced by alkaloids, which are toxic
Sweet.
Most sensitive receptors on tip of tongue. Shares lowest sensitivity with salty. Sugars, some carbohydrates, and some proteins
Umami :
“Savory” ; Scattered sensitivity. Caused by amino acids such as glutamate, binding to receptors
What 3 things influence taste?
Texture affects the perception of taste
Temperature affects taste perception
taste influenced by olfaction
What 3 things can influence the perception of taste?
texture, temperature, olfaction
which taste bud is the most sensitive?
bitter
What are the 3 major parts of olfaction?
-olfactory tract
-olfactory bulb
-olfactory receptive
olfactory tract
The olfactory tract connects the olfactory bulb to the remainder of the cerebral cortex, including amygladla
olfactory bulb
Olfactory sensory neurons extend their axons solely to the olfactory bulb, which is dedicated to odor information processing
olfactory receptive neurons
bipolar neurons that are activated when airborne molecules in inspired air bind to olfactory receptors (ORs) expressed on their cilia.
odorant receptors are found where?
cilia of olfactory receptor cells (neurons)
Explain the steps in olfaction
- Cilia (olfactory hairs) of olfactory neuron are embedded in mucus. Odorants
dissolve in mucus.
2.odorant molecules bind to odorant receptors - axons of olfactory cell with same receptor, form synapses with mitral cells in glomeruli
- multiple axons synapse with a mitral cell
5.Mitral cell axons comprise the olfactory tract and transmit action potentials
t/F one olfactory cell responds to one odorant
false: can respond to a set of different odorants
However each olfactory cell receptor expresses one olfactory cell
glomeruli are found where?
located on the olfactory bulb
olfactory vesicles
dendrites of olfactory neurons have enlarged ends
cilia are also called
(olfactory hairs)
Cilia (olfactory hairs) of olfactory neuron are embedded
mucus
t/F One receptor may respond to more than one type of odor
true
olfactory bulb can also connect to what system?
Olfactory bulbs also connect to limbic system-signals can elicit
emotional/visceral response
only major sense that does not go through thalamus
Olfaction: Information goes to olfactory cortex of the frontal lobe without going
through thalamus
Three regions in frontal lobe affect
conscious perception of smell and
interact with limbic system
What are the three regions in frontal lobe?
-Lateral olfactory area
– Medial olfactory area:
– Intermediate olfactory area:
Lateral olfactory area:
conscious perception of smell
-regions in frontal lobe
Medial olfactory area:
visceral and emotional reactions to odors
-regions in frontal lobe
Intermediate olfactory area:
effect modification of incoming information.
-regions in frontal lobe
thermoreceptors
consist of free nerve endings
Nociceptors
Detect stimuli that can damage body tissues;resulting in the sensation of pain
Two axons that transmit pain
Glutamate releasing: sharp, localized pain
Substance P: dull, aching, not well localized
