Exam 7: February 27 - March 3 Flashcards
what information does your vestibular system give?
it’s the part of your sensory NS that tells you about your head position and motion
what receptors does your vestibular system use?
mechanoreceptors
stereocilia specifically
what are the components of your vestibular system?
1) semicircular canals
2) otolith organs
how many semicircular canals do you have?
3
what do your semicircular canals help with? which vectors?
help you tell how your head is moving in a 3D space because each plane gives you a vector of movement and you do vector addition
rotation, acceleration, and deceleration
what is the reference that your simicircular canals use?
when you solve this 3 plane problem, you get the line that you’re moving but you don’t know if it’s positive or negative direction….you need a reference!
Gravity is always working on us and will tell us which way is “down”
what does otolith mean?
“lith” means stone
“oto” means ear
if you have rocks in your ears and you tilt you head, the rocks would follow gravity and roll so rocks in your head would be helpful because they would tell us which way gravity is pulling on us
how many otolith organs do you have? why do you have that specific number? what are they called?
2! because your head can tilt side to side or back and forth so you need one for each
utricle and saccule
what are the otolith organs made of?
your utricle and saccule are calcium stones
when do your otolith organs have difficulty determining orientation? how do you fix this?
gravity has a low impact on us when we’re in water
when someone is under water and gets disoriented they have a hard time figuring out which way is up because we’re buoyant in water so gravity doesn’t pull down and the rocks don’t roll right
so how do you solve the problem of which way is up? Bubbles! Follow the bubbles because they will always go towards the surface
what do your otolith organs give you information about?
your otolith organs give you the information of acceleration relative to gravity
the rocks can only roll so far so you only get the initial component
the rocks are about changes in motion, not constant motion – kind of like cans in your car trunk
with the use of your semicircular canals you know if you’re staying in that position
what information does your chemosensory system give?
it’s a part of your sensory nervous system that tells us about dissolved chemicals
our eyes are filled with fluid
we breath in air and bring things into our mouth but we have to dissolve them to be able to register
what receptors does the chemosensory system use?
chemoreceptors
what are the components of the chemosensory system?
taste and smell
internal and external!!
this is just the way we gather information from the outside – how the chemicals are changing around us or how they’re changing inside us – so these are just the external measurements
internal: pH, O2, CO2 levels – make sure we’re staying in SS and are in homeostasis
what is another name for taste?
gustation?
where do we find the chemoreceptors associated with taste?
Your mouth overall because you have your tongue and the back of your throat too
you also have receptors in your GI track and your lungs as well so that’s why when you breath sometimes you feel like you taste it
what causes an aftertaste with food?
there are different chemoreceptors in the back of your throat
what helps to increase the number of taste receptors?
where we have these receptors, there’s lots of surface area
our tongue isn’t nice and smooth, it’s bumpy so that you can have lots of receptors (10,000 taste receptors in association)
why do we put stuff in our mouth?
it’s most likely going to end up going in to your digestive track
you need to decide if you want to swallow something or spit it back up
what are primary taste receptors?
things that are critical to maintaining homeostasis are important so for knowing if it’s something you want to digest
what are the 6 primary taste receptors?
1) salty
2) sour
3) sweet
4) bitter
5) umami
6) fat
what is your salty primary taste receptor do?
need Na for membrane potential, action potential, your nervous system – historically sodium was lacking in our environment – Na acts on the receptors and causes an influx of Na which activates membrane potential
it gives us information about a compound that is of critical importance so we know it’s something we want to swallow and we need more of
we’ve become successful at accumulating salt from our environment but back in time we weren’t and used salt as a monetary unit
why do you need sodium?
need Na for membrane potential, action potential, your nervous system
what is your sour primary taste receptor?
H+ blocks normal K+ movement
H+ impacts the ability of the regular movement of K into these receptors and therefore impacts membrane potential of these receptors
when would we want sour foods?
sour is important for pH regulation of blood: we don’t want to be acidic or basic
if we’re lacking in H+ we’ll want sour things but if we’re already acidic we won’t want to take in sour things
it all depends on your current situation
what does a sour taste indicate?
another thing this sour taste tells us is when proteins break down they release H+ so a sour taste typically indicates that that food is spoiled
what does your sweet primary receptor tell you? what activates these receptors?
binding of glucose activates these receptors
we need the glucose to do glycolysis and feed into Krebs cycle/ETC
we can run these processes off proteins and fats but it’s not as efficient – this has changed in our history but we’ve also become efficient at extracting sugar out of our environment
why do we need glucose?
to do glycolysis and feed into Krebs cycle/ETC
what does your bitter primary taste receptor tell you?
it’s unlike the other 5 categories in that it’s a group category
it’s a grouping of at least 30 compounds that bind to a similar Rs so they historically all get us the same response
they’re typically alkaloids (caffeine) and toxins that bind to these bitter receptors
why do bitter things taste bitter?
the compounds that bind to bitter receptors are typically alkaloids (caffeine) and toxins
this makes sense because alkaloids play with pH and toxins are bad
when you taste something bitter you don’t ingest it typically – this is why a lot of pharmaceuticals don’t have a good taste because they’re toxins which makes it hard to give medicine to kids
historically bitter things you avoid ingesting so you avoid toxins and don’t have a pH change – how we deal with them now we can consciously say that it’s okay because it might be healthy actually like kale
what does umami mean?
a pleasant or savory taste in Japanese
what is the umami primary taste receptor?
it’s when you can’t put a name to it when you’re eating it but wow it tastes good - it’s most likely your umami receptors responding
what activates umami receptors?
binding of glutamate is what activates umami receptors
what makes food taste better?
monosulfate glutamate = MSG
binding of glutamate compounds makes food taste good!
why do we like bacon?
glutamate is needed for Krebs
having enough glutamate helps keep aerobic cell metabolism working properly
we also know that lots of our AA can act as neurotransmitter so therefore Glu also acts as a NT so without it there’s nervous system communication problems and ATP production problems
umami are also a protein indicator
what can umami receptors also be an indicator for?
umami are also a portion indicator
what activates fat primary taste receptors?
binding of a fat that activates these receptors
how that’s happening is still being worked out
it’s about a critical need and that it’s something historically was quite low in the environment – we can turn fats into energy!
what’s another name for smell?
olfaction
where does olfaction happen?
3 cmˆ2 patch on the roof of your nasal cavity
not wide spread like taste receptors
which receptors does smell use?
chemoreceptors
5 million receptors with 1000 types in this small little patch of area so we don’t really categorize or group them
what is your sense of smell?
it’s about detecting changes in the environment but you don’t have intimate contact with it or bring it into your body
what happens when you can’t smell?
when your nose is a wet area so when your nose dries out your lose your sense of smell because you need the moisture to dissolve
how long do your smell receptors last?
2 months = high turnover area
how do receptors in the smell and taste turn over?
when individual receptors in our mouth turnover but the categories stay the same
with our sense of smell we add and take away categories all the time
what is being nose blind?
your nose receptors have a high turnover rate and you add and take away categories of receptors all the time
being nose blind to things is if you’re around something all the time, you’ll put away the receptors it and literally stop smelling it like in the febrile commercials
if it’s always in your environment, it’s not interesting like how you don’t need to know that you’re wearing clothes – this is why you need to change your perfume and cologne regularly because you stop realizing how much you’re putting on
how do you register smells?
your olfactory bulb is the patch in the roof of our nasal cavity
at this spot we’re just picking up the information, we do some initial processing with it so it’s your initial sorting
how do you process smell?
you initially sort smells at the olfactory bulb
this initial sort then goes to a section of your brain in your cerebral cortex called your primary olfactory cortex which is your secondary processing center that starts getting you to act on what you’ve smelled before you even consciously register it such as getting closer or farther away from the source
when you become conscious of those smells its because of processing done in your orbitofrontal cortex in your cerebral cortex
what is the primary olfactory cortex?
subconscious coordination with behavior
what happens when you become conscious of a smell?
when you become conscious of those smells it’s because of processing done in your orbitofrontal cortex in your cerebral cortex
this one gives you conscious knowledge of that particular smell and now you register it
you might already be reacting to it before this conscious registering happens which gives you more detail of what you’re detecting
what is your vomeronasal organ?
it’s related to olfactory
it’s not about general chemicals being registered like in olfaction, it’s about chemicals being registered from another organism = receiving signals that are released from another human and come to you to act on your cells
they’re between person signals instead of between your own cells which are called pheromones
you respond to them and recognize and give off certain pheromones that tell information about you and get other individuals to respond to that information you’re giving them – it’s not within smell, it’s similar though
what is perception?
it’s not identical to detection
ex. obvious case and point is smell because we’re reacting to smell before we consciously know that they’re even there
ex. pheromones we don’t even know they’re there but we’re responding to them
how does perception work?
o Within the interpretation of these signals, the brain sees no reason to keep them as separate entities and often merges them together
you have 6 categories of taste receptors but when your nose gets stuffed up things don’t taste the same because what we perceive as the sense of taste is actually a combination of smelling it, tasting it, hearing it, and seeing it
it’s not just about how it hits and individual’s tongue, it’s also about presentation because if it looks great it’ll influence how you feel about it when you taste it – if you get a bag of chips but can’t hear a crunch, you perceive that it’s stale
what kind of process is the interpretation of signals?
the interpretation of signals is a cerebral process
so when you drink your taste and perception change…
what are consequences of perception?
we often combine signals so you have to be careful about saying something is just from one area because you’re likely responding to multiple things that are happening at that time
we are often very unconsciously acting on the signals that we gather where as we think we’re only consciously acting on them – guys can pick up on signals girls are sending based on what time in her cycle she’s in
what does your somatic nervous system do?
the somatic NS controls skeletal muscles only, not cardiac or smooth muscle
which muscles are striated? which are not?
skeletal and cardiac are striated
smooth muscles are not striated
does your mouth or nose have more receptors?
your mouth has less receptors and less types of receptors than your nose
which muscles are voluntary vs involuntary?
skeletal muscle is under voluntary control, we are making them move in a conscious matter, it’s not under the autonomic nervous system
our cardiac and smooth muscle (size of blood vessels, GI tract) are involuntary
what do our different types of muscles do?
skeletal muscles move bonds
cardiac muscles are changes in heart volume
smooth muscles are changes in our organ volume
what is the organization of a muscle?
cells, tissues, organs, and organ systems are the levels of organization
what is your muscle?
your muscle is an organ!
what are the units in a muscle?
myfibers → myofibril → myofilaments
myofiber is the container
the myofiber is the straws inside of it
the myofilaments are the stripes on the straw
