Olfaction And Gustation Flashcards
Define what pheromones are and how they impact other organisms.
Pheromones are specialized olfactory chemicals that act to communicate or elicit a response of an individual of the same species.
How are pheromones detected?
They are detected by the accessory olfactory epithelium, a segment of the olfactory epithelium, detects the pheromones.
True or false, after pheromones are detected by the accessory olfactory epithelium, the signal is sent to the olfactory bulb
False, once the pheromones are detected by the accessory olfactory epithelium, the signal is sent to the ACCESSORY olfactory bulb
Describe the travel of smell signals after the vomeronasal systems receive pheromone signals.
It sends signals to a glomerulus in the olfactory bulb. Then it is projected from the glomerulus and sent to a mitral cell and then relayed to the brain.
After the gustatory cortex has processed the information, it has the ability to send the signal to the limbic system structures such as the amygdala. What is the significance of the amygdala in pheromone processing?
The amygdala is involved in emotion, aggression, and mating. The organism can then regulate the behavior based on the pheromones they are detecting in the environment
Mitral Cells are also known as:
A. Mitral Valve
B. Tuft Valve
C. Tuft cell
D. Bicupsid cells
C. Tuft Cells.
Much like normal olfactory cells, how does the accessory olfactory cells depolarize?
Both have G coupled protein receptors that cause the G protein to dissociate from the membrane to elicit ion channels to open to allow + ions to flow into the cell to depolarize the cell
True or False: Humans have no ability to process pheromones.
True. Even though humans don’t have the ability to detect and process pheromones, they still have olfactory bulbs.
As Angelie is eating a cake, how is the olfactory system also functioning as well?
Chewing causes the chemicals to go up the nose and bind to olfactory bulbs. Receptors here are also stimulated as well. Therefore eating is a combination of the gustatory and olfactory system.
Catalina is feeling sick today and she says she doesn’t want to eat because nothing tastes good to her. Why is this phenomenon occurring?
Because she is sick, she is experiencing nasal congestion. This prevents her olfactory epithelium cells from capturing the incoming chemicals and therefore her experience in eating is not enriched as it normally would.
The glomerulus of the olfactory bulb:
A. Receives a single information from a single nerve
B. Receives many information from a single nerve
C. Receives many information from many nerves
D. Receives a single information from many nerves
D. Receives a single type of information from many nerves detecting the same information. These nerves are randomly dispersed in the olfactory epithelium
What is the importance of the many glomerulus synapsing onto one tuft cell in the olfactory bulb?
This is important as it is easier to have a few axons travel to the brain than having 1000+ axons sent to the brain at once
The depolarization of an olfactory nerve occurs only when…
A chemical binds on the receptor to cause a G couple protein to dissociate and produce other effects.
There are 5 main tastes detected by the tongue. Associate which specific chemical causes elicits the perception of umami and sweet.
Umami - Glutamate
Sweet - glucose or other sugars
The old dogma of taste consists of a taste map, defining different portions of the tongue to a particular taste. What is the new theory of taste?
Papillae consisting of receptors are sprinkled all over the tongue. Different portions of the tongue have different concentrations of different types of taste buds.
Anteriorly - increase concentration of fungiform papillae
Lateral - some foliate papillae
Posterior - Circumvallate papillae
Differentiate the difference between circumvallate and foliate papillae
Circumvallate has a wider superior border than the foliate papillae and contains more than 100 taste buds in each papillae. Both have taste buds on the lateral sides of the papillae
Describe the travel of a chemical stimulus after it is transduced in the olfactory system.
Chemical travels up the nostrils => Binds to receptors on the olfactory epithelium and signal is transduced to electrical => travels up the cribriform plate to the olfactory bulb to the glomerulus => Signals synapse to the mitral cells => Signals sent to the olfactory cortex through the olfactory tract
Describe the relationship between papillae and taste buds.
Papillae are the engorged grooves of the tongue. These papillae contains many taste buds.
Circumvallate papillae - 100+ taste buds
Fungiform papillae - 3-5 taste buds
True or False - Taste buds consist of neuronal receptor that have the ability to detect all 5 tastes
False. These receptors are specialized epithelial cells, therefore they have to synapse onto other neuronal cells. Each taste bud does have the ability to detect all 5 tastants
Like many cortices processing other information, how is the gustatory cortex organized?
The gustatory cortex is also divided into different regions to process only a certain type of smell. (no need to know specifics)
You’re eating a piece of cake, and two different receptors are stimulated on different portions of the tongue by the sugar. Describe their detection and signal travel from the tongue to the brain
Both are activated by glucose and send their signals up to the brain. Along the way, the the axons bundle to form a tract in a similar pathway up to the gustatory cortex
In an experiment, to test the labeled line model, you have inserted umami receptors onto a salt cell in a dog. Based on the labeled line model, what is the expected outcome after the dog was given some meat.
The labeled line model states that taste information does not mix from detection to the brain. Because the cell is a salt cell, the signal will be sent to the brain without interruption and the brain won’t be able to distinguish the umami flavor of the meat.
In an experiment, to test the labeled line model, you have inserted sweet receptors onto a salt cell in a mouse. Based on the labeled line model, what is the expected outcome after the mouse has had some salt.
No signals would be detected. The sweet receptors would not bind with the salt and the cell then won’t fire. Therefore the brain won’t interpret anything even though the actual stimulus is present
How are the 5 different tastes (salty, sweet, sour, umami, and bitter) sensed by the tongue
A. There are areas of the tongue whose taste buds are sensitive to one of the five flavors
B. There are areas of the tongue whose taste buds are sensitive to one of the five flavors
C. Each taste bud is composed of multiple cells, that combine to sense the 5 flavors
D. Each taste bud is composed of multiple cells, that combine to sense 1 of the 5 flavors
C. Each taste bud is composed of multiple cells, that combine to sense the 5 flavors
Anosmia is the partial or complete lost of smell, which can affect taste as well. What are the causes of anosmia?
Trauma, respiratory infections, and aging
The most primitive sensory receptors are…
Chemoreceptors. Though the most primitive, they are the most fundamental as well as they are important in activating and creating memories, alerting individuals of danger, and enriching life of sensory
The sense of taste and smell are sharpest at birth. How do neonates utilize the sense of smell?
They utilize the sense of smell to orient themselves, such as finding their mother
The sense of taste and smell are sharpest at birth. How do neonates utilize the sense of taste?
They can taste difference in mother’s milk to others and this allows them to find their proper source which ensures their safety.
What requirement does chemicals have to have in order to be detected by the nose?
These chemicals have to be volatile (in a gaseous state) in order to travel up the nose
Millions of olfactory sensory neurons exist in the olfactory bulb. What supports these cells in the epithelium?
The columnar supporting cells
True or False: Each olfactory sensory neuron specializes to detect on kind of smell.
True.
About 40 million olfactory sensory neurons help us identify smells. How many different smells can be detected as a result? A. 100,000,000 B. 10,000,000 C. 100,000 D. 10,000
D. 10,000 smells plus or minus a deviation, but the number is around here.
In latin, Glomus means a ball of yarn. How does this help distinguish the role of the glomerulus in the olfactory bulb?
The glomerulus looks much like one, due to the tangle of fibers and because it relays information to a mitral cell, it functions as a relay station
Once the information has been processed in the olfactory cortex, it can be funneled to one of two places. What is the purpose of sending information to the frontal lobe?
It helps the individual to consciously identify the smell.
Once the information has been processed in the olfactory cortex, it can be funneled to one of two places. What is the purpose of sending information to the hypothalamus?
Information sent to the limbic system (hypothalamus, amygdala, etc) is associated with emotions. These pathways are fast, intense, and triggers memories if the odor is associated with memories or experiences
True or False: Taste is 50% smell
False. Taste is 80% smell
While holding your nose, you eat a lemon and a lime. What are you able to detect? What are you not able to detect?
Because smell plays a large portion of taste (80%), with no smell, taste will be muted. Smell also plays a large role in distinguishing differences, therefore you’ll be able to taste sour in both, you won’t be able to taste the difference between a lime and lemon
After some exposure to some radioactivity, a dog has been discovered to have lost all of its basal cells in the tastebuds. What are your expectations?
Basal cells in the tastebuds are stem cells to replace gustatory cells in the papillae. Without the basal cells, the gustatory cells (receptors of tastants) won’t regenerate if it should die and lost of taste would occur
After being in the oven for 30 minutes, you finally remove a pizza. In a hurry to taste the pizza, Juan takes a huge bite, burning his tongue. What has occurred to the taste buds? What should happen in a normal setting?
The heat has caused the gustatory cells to die, therefore he should not be able to taste food in this portion of his tongue. The basal cells should regenerate to become new gustatory cells in about a week.
True or false: There are 5 types of basal cells: Umami, salt, sweet, sour, and bitter.
False. There are 5 types of gustatory cells: Umami, salt, sweet, sour, and bitter.
There are 5 main tastes detected by the tongue. Associate which specific chemical causes elicits the perception of salt and sour tastes.
Salty - Na+ ions
Sour - H+
Which cranial nerve(s) do gustatory information travel up in order to reach the gustatory cortex?
The signal is relayed through neurons via CN VII, IX, and X to the gustatory cortex
After the brain interprets taste information, what occurs?
A. Induce reflexive chewing
B. Induce reflexive swallowing
C. Secrete proteins
D. Send information to the limbic system
C. Secrete proteins. It begins to release digestive enzymes in saliva, gastric juices in stomach to help break down the particles
Consciousness is the awareness of oneself and their environment, ranging from what state to what?
Consciousness captures from alertness to sleep. Therefore sleep is a part of consciousness as well.
Differentiate daydreaming to drowsiness in terms of consciousness.
Both are states of consciousness in which they can with come about naturally or be induced by light meditation
Daydreaming is a state of awakeness and awareness of the world. It is associated with unfocused relaxation
Drowsiness is a state of close to sleep, but still semi aware of the world
What is one stage of consciousness not often thought about when defining consciousness. Why is it still considered a part of being aware about one’s self and the environment?
Sleep is a state of consciousness too that is often not thought about. While individuals may not be aware of shifting from one state of consciousness to another, the brain is able to know this through sets of neurons in the CNS that fire rhythmically, leading to neural oscillations
In a sleep study, you are assessing your patient’s neuronal oscillations and see that these waves are occurring at a 6 hz. What frequency is this? What type of consciousness are they currently at?
These are Theta waves, θ. These types of waves, from 4 - 7 hz, are associated with drowsiness and these patterns can be seen right after a person has just fallen asleep. Therefore the sleep is light
After a traumatic fall onto his head, your 8 year old patient is brought into the ER by his parents. All his vitals are normal: HR of 60, BP of 110/60. You order an EEG to double check all neuronal functions are performing normally and your intern brings you a chart with waves of 10 hz. What is his current state of consciousness?
He is in a state of daydreaming. Alpha waves, α, associated with this type of consciousness are from 8 - 18hz
In a lab experiment you are attempting to cause your mouse to be fully aroused by electroshock. At what point of the frequencies of the EEG produced by the mouse, should you stop the experiment
Once the EEG demonstrates Beta waves, β, oscillates from 12 - 30 hz. These wave patterns are associated with alertness. `
True or false: There are 4 different stages of sleep, and the brain cycles through these stages every 120 minutes.
False. There are 4 stages of sleep: NonREM (N)1, N2, N3, and REM. However these stages are cycled through every 90 minutes
Waves of sleep are often shared with the same waves seen during awake states. N1 sleep shares waves with what awake stage?
Theta waves, 4 - 7 hz are shared in the N1 Sleep, which is also seen in drowsiness.
It’s bedtime. You are laying on top of Juan’s chest when his arm and legs start jerking. What stage of sleep is he currently in? What hz are the brain waves he is currently producing? What is the medical term for this phenomenon?
Juan is currently in his N1 stage, with theta waves (θ) oscillating from 4 -7 hz. HE is currently experiencing hypnic jerks
Angelie and you are watching a movie and you notice she is slightly dozing off. She jerks awake and says she saw very bright lights and thinks it was an alien. What phenomenon did she just experience? What portion of sleep was she in when this phenomenon occurred?
She was experiencing hypnagogic hallucinations, which is seen in N1 sleep stages.
You can’t sleep and it is the middle of the night. You reach over to Juan and slightly brush his arm, but he doesn’t stir and continues to snore. What portion of sleep is he currently in right now? What is preventing him from noticing your touch?
He’s currently sleeping in the N2 sleep stage. During these stages, it is slightly harder to wake the person up. The touch induces K complexes that appear on the EEGs. These complexes are much like the QRS complexes in ECGs and occur both naturally and can be induced. This may be associated with suppressing cortical arousal from non threatening stimuli to keep the person asleep
What is one theory about K complexes and why they exist?
One theory defends K complexes are important to consolidate memories into long term.
