Nervous System Unit Final Flashcards
what type of pigment is in cones and what is it composed of
photopsin which is composed of opsin and retinal
what are the projections on the hair cells called
stereocilia
what does the lens do
focuses the light rays that enter through the pupil onto the retina
how do the semicircular canals work
there is a bulge at the base of each canal that contains stereocilia of the hair cells stuck in a jelly-like covering called a cupula. when the head rotates fluid inside the canal moves and bends the stereocilia which causes the hair cells to send rotational information to the brain
what happens to the basilar membrane when your ears perceive loud noises
the louder the noise, the more pressure that is put on the basilar membrane
what protects the brain
the skull and meninges
what are the two divisions of the motor pathways
somatic nervous system and autonomic nervous system
examples of chemoreceptors receptors (4)
taste buds on the tongue, olfactory receptors in the nose, osmoreceptors in the hypothalamus, receptors in the carotid artery and aorta
is the external surface of the tympanum concave or convex
concave
whats the fovea centralis
small area located at the back of the eye in the centre of the retina that contains a high density of cones
what does the lateral ventricle do
produce and store cerebrospinal fluid
what does the sclera do (3)
it protects the eye, maintains the eyes shape and serves as a key attachement point for different muscles
true or false: if something has a sympathetic system it also has a parasympathetic nervous system
true, both systems are always present
is the somatic nervous system voluntary or involuntary
voluntary
difference between the functions of the fovea and the macula
the fovea provides sharp acute vision where as the macula provides sharp central vision
whats the pupil
the black opening in the middle of the iris
what is the function of the pinna
to collect sound waves, enhance their vibration and focus them into the auditory canal
what causes myopia
when the eye is elongates so the focusses light falls in front of the retina instead of on the photoreceptors
whats the optic disk
small round area at the back of the eye where the retina and optic nerve connect that does not contain any photoreceptors
what does the blood-brain barrier do
protects the brain and supplies the brain with nutrients and oxygen
what are the main structures of the hindbrain
pons, cerebellum and the medulla oblongata
what is gravitational equilibrium
the balance required when moving forward and backward
what is sulcus
the groves in between the gyri on the surface of the brain
whats hyperopia
when they can clearly see objects that are far away but cannot clearly focus on objects close up
what does the optic disk do (3)
- connects the retina to the optic nerve
- allows for vision signals to be transferred from the retina to the brain
- creates a blindspot within someone’s vision
what is parasympathetic nervous system referred to as
“rest and digest”
where are brocas area and wernickes area located
left side of the cerebral cortex
what cause hyperopia
when the eyeball is too short so the light rays do not meet before they reach the retina causing the image to be focused behind the retina
what are sound waves
small fluctuations in air pressure
what neurotransmitter is involved in the sympathetic division of the nervous system
norepinephrine
what does the corpus collosum do
connects the left and right hemispheres of teh brain and allows them to communicate with each other
what two things form convolutions
gyri and sulcus
where is the organ of corti located
the middle chamber of the cochlea
what are the most common cones to be impacted by colour blindness
the red and green gones
what type of pigment is in rods and what is it composed of
rhodopsin which is composed of retinal and opsin
where is the amygdala located
underneath the temporal lobe
what is the temporal lobe primarily responsible for (3)
interpreting hearing, taste and smell
what is the relationship between age and melatonin levels
melatonin is released 2 hours later at night in a teen brain than adults and stays in their system longer
whats vitreous humor
a jelly-like fluid located in the posterior chamber of the eye
what is sensation
when neural impulses arrive at the cerebral cortex; same process for everybody
whats another word for volume (related to hearing)
amplitude
whats the oval window
the membrane-covered opening in the wall of the inner ear that connects the ossicles of the middle ear to the cochlea
what do the semicircular canals do
they contain mechanoreceptors that detect head and body rotation
is the autonomic system voluntary or involuntary
involuntary
what is the sclera
the white, tough, fibrous tissue that makes up the external layer of the eye
whats the macula
a small round area of the retina located in the retinas centre at the back of the eye
what are cranial nerves
the nerves that go to the brain
where is the hippocampus located
right above each ear in the temporal lobe, deep beneath the cerebral cortex
what is the order of the meninges from closest to skull to closest to brain
dura mater, arachnoid, pia mater
in general, what is the cerebrum responsible for
- contains the centers for intellect, memory, consciousness and language
- interprets and controls the response to sensory information
whats mixed hearing loss
a combination of conductive and nerve hearing loss
what are the rods and cones
types of light sensitive photoreceptor located in the retina of the eye
where are the olfactory bulbs located
located by the nasal cavity underneath the frontal lobe
what is the cerebral cortex
the layer of tissue that covers the cerebrum, underneath the meninges
how do the ossicles work
each bone acts as a lever for the next so that a small movement in one results in a larger movement in the next
whats the lens
clear, curved, flexible structure located at the front of the eye behind the pupil
what does the fovea centralis do
primary area of the eye that is responsible for the production of sharp images and for providing acute vision
whats glaucoma
when the ducts that drain aqueous humor become plugged and pressure builds up in the eye, causing the blood vessels to rupture resulting in the eye cells deteriorating due to a lack of oxygen and nutrients
what is the occipital lobe primarily responsible for
processing visual information from the eyes
where is the thalamus located
sits at the base of the forebrain
what is the middle ear
air filled space that is bordered on one side by the tympanum
what is perception
process unique to each person that results from how the cerebral cortex interprets the meaning of sensory information
where do high frequencies stimulate
hair cells closest to the oval window
whats does the vitreous humour do (3)
- supports the surrounding cells in the eye
- maintains the shape of the eye
- helps to keep the retina in place and flat at the back of the eye
where is the pons located
above and in front of the medulla oblongata in the brain stem
where is cerebrospinal fluid located
between the pia mater and the arachnoid membrane, as well as in the ventricles of the brain
what are the 3 main types of hearing loss
conductive, nerve/sensorineural, mixed
whats the ciliary body and what does it do
extension of the iris that produces aqueous humor
what doe the rods do (2)
- they are sensitive to the intensity of light and are responsible for enabling vision in areas of lower lighting
- create peripheral vision
what are the main functions of the right hemisphere of the brain (7)
- sensory stimulus received from the left side of teh body
- motor control of the left side of the body
- holistic and intuitive thinking
- visual spatial skills/spatial awareness
- artistic abilities and creativity
- nonverbal memory
- visual and emotional processing
what are the 4 different categories of sensory receptors
photoreceptors, mechanoreceptors, chemoreceptors, thermoreceptors
what does rotational equilibrium refer too
head and body rotation
what is located along the base of the organ of corti
the basilar membrane
what neurotransmitter is involved in the parasympathetic division of the nervous system
acetylcholine
what are convolutions
the prominent ridges and folds observed on the brains surface
what does the retina do (2)
processes the light rays and images that pass through the cornea and converts them into electrical signals for the brain to process
what is the cerebral cortex made of
outer 4cm of the cerebrum that is mostly grey matter made up of densely packed neuron cell bodies and their dendrites with white ,atter containing the axons of cortical neurons located deep inside
whats another name for the skull
cranium
what are some responses to the activation of the sympathetic nervous system (9)
- inhibits tears
- dilates pupils
- inhibits salivation
- dilates air passages
- speeds up heart rate
- stimulates liver to release glucose
- stimulates adrenal secretion
- inhibits activity of the kidneys, stomach and pancreas
- decreases intestinal activity
what does the pituitary gland do (2)
- produces and releases various hormones that regulate many critical body functions
- effectively controls the activity of other endocrine glands and acts as the master endocrine gland of the body
whats the tympanum
round, elastic surface that vibrates when hit by sound waves
what are the 4 main things the frontal lobe does
- controls higher mental activities including learning, memory, logic, foresight, creativity and some emotions
- includes the motor cortex which controls voluntary movements
- has a region that controls intelligence and personality
- Decision-making and planning
what are the two divisions of the autonomic nervous system
sympathetic nervous system and parasympathetic nervous system
what is the organ of corti known as
the organ of hearing
what is the parietal lobe mainly responsible for and what cortex does it include
- interpreting sensations from various body areas revolving around touch and pressure
- includes the sensory cortex
whats dilation
when the pupils get larger to let more light in
what does the midbrain do (2)
- relays visual and auditory information between areas of the hindbrain and forebrain
- plays a role in eye movement and control of skeletal muscles
what does the aqueous humor do (2)
- provides nutrients and oxygen to the lens, cornea and other surrounding cells
- maintaining the shape of the cornea through the pressure of the fluid
how does the image appear in the occipital lobe and why
the image is split because the left optic tract carries information about the right portion of the visual field and the right optic tract carries information about the left visual field
how is the air pressure kept equal on both sides of the tympanic membrane
by the eustachian tube which is connected to the throat
what are thermoreceptors
receptors located in the skin to detect heat and cold
whre is the pituitary gland located
just below the hypothalamus
where is the vestibule located
in the inner ear in the wide part around the cochlea between the semicircular canals above and before the cochlea starts to spiral
where do parasympathetic nerves originate from
the brain
what is cognition
the mental process that includes the attention of working memory, comprehending and producing language, calculating, reasoning, problem solving and decision making
what does the choroid layer do (2)
- contains blood vessels that brin oxygen and nutrients to the eye
- absorbs any scattered light rays that weren’t detected by the retina
where are the utricle and saccule located
in the fluid filled vestibule of the inner ear
what do the olfactory bulbs do
receive and interpret information about smell
what are the 3 main structures in the inner ear
semicircular canals, the vestibule and the choclea
what does the amygdala do (3)
- involved in sexual and emotional behavior
- sensitive to sex hormones and adrenaline
- seat of anger
what is your sympathetic nervous system referred to as
“fight or flight”
what are the three different types of cones and how do they work (BASIC)
red, blue and green
- they each detect a different wavelength of light
what is the corpus callosum formed by
a bundle of white matter
whats accommodation
The ability of the lens to change shape in order to focus images at a different distance clearly on the retina
whats the tectorial membrane
the membrane on the top portion of the organ and corti which the hair cells flex against after being moved by the basilar membrane
what are the two types of tissue that the central nervous system is composed of
grey matter and white matter
what stimulates chemoreceptors
chemicals
where is the cerebellum located/what does it look like
walnut shaped structure located below and largely behind the cerebrum
what does the pupil do (2)
- allows light to enter the eye
- controls the amount of light that enters the eye
what shape does the lens form when its focusing on objects close up and how
the ciliary muscles contract and the suspensory ligaments relax causing the lens to become more rounded (convex)
what are some responses to the activation of the parasympathetic nervous system (8)
- stimulates tears
- constricts pupils
- stimulates salivation
- constricts bronchioles
- slows heart rate
- stimulates gallbladder to release bile
- increases activity of stomach and pancreas
- increases intestinal activity
what are the two divisions of the peripheral nervous system
sensory nerves/pathways and motor nerves/pathways
whats astigmatism
when there is uneven curvature on part of the cornea making it so that the cornea cannot bend light rays so that the meet at the correct focal point do to its asymmetry
where is the hypothalamus located
lies just below the thalamus
when does macular degeneration occur and what does this cause
when the cones are destroyed due to thickened choroid vessels that no longer function as they should; results in the blurring of or the development of a blind spot in the central vision
how is the auditory canal protected
its lined with hairs and cells that secrete cerumen
what do mechanoreceptors do
respond to mechanical forces from some sort of pressure
what glands produce tears and what is there function
the lacrimal glands produce tears to keep the eyes moist
whats cataracts
when the protein structure of the lens starts to degenerate, making it cloudy with grey-white spots that prevent light from passing through as well
why is the surface of the cerebrum highly convoluted
to increase the surface area for nerve cell bodies
what does the thalamus do
provides connections between the forebrain and hindbrain and between areas of the sensory system and the cerebellum
what does the hippocampus do (3)
- produces new neurons
- involved in long term memory formation
- transforms reinforced short-term memories into long-term memories
how does the brain develop
from back to front
what is gyri
the ridges on the cerebral cortex
whats the basilar membrane
the membrane that lies along the base of the organ of corti and is attached to the hair cells
what are hair cells
sensory mechanoreceptors attached to the basilar membrane in the organ of corti within the inner ear
whats the optic disc also known as
blindspot
why can the middle ear significantly amplify and concentrate the sound vibrations
because the tympanum is significantly larger then the oval window
what is the pinna/auricle
outside flap of the ear that is made of cartilage
what are proprioceptors
mechanoreceptors located in and near the muscles to provide information about body position and movement
whats colour blindness
an inherited condition caused by a lack or deficiency in particular cones that makes it difficult or impossible to distinguish between certain colours
how does the cochlea work
the stapes strikes and vibrates the oval window which creates pressure waves in the fluid filled cochlea. these make the basilar membrane move up and down which causes the stereocilia of the hair cells to bend against the tectorial membrane. The hair cells synapse with the nerve fibers of the auditory nerve, sense the bending of the stereocilia and relay this message to the nerves which sends the impulse to the temporal lobe of the brain
whats the retina
the innermost layer of the eye that contains the rods and cones
whats the blood-brain barrier
separation of the blood and central nervous system
what categories of nerves are involved in the sympathetic nervous system
cervical, thoracic and lumbar nerves
what is the auditory canal and what is its function
channel leading to the ear drum in the middle ear that effectively amplifies sound
what decibel level damages the hair cells
80 dB or higher
what does the macula do
- processes what you see directly in front of you
- provides sharp central vision
what categories of nerves are involved in the parasympathetic nervous system
cranial, sacral and vagus nerves
what do the meninges do
surround and protect the brain and spinal cord
what are nerves
a bundle/bunch of neurons
whats the choroid layer and where is it located
a vascular membrane that makes up the intermediate layer of the eye and is located between the sclera and the retina
what are the 3 major structures in the inner ear to help us stand upright and move without losing our balance
semicircular canals, utricle and saccule
what are 3 examples of mechanoreceptors
hair cells in the ear for balance and hearing, proprioceptors in the muscles, different mechanoreceptors in the skin
how many cranial nerves are there
12
what is the lateral ventrical
cavities within the brain
true or false: rods need multiple photons of light to be stimulated
false –> rods are extremely sensitive to light and can be stimulated by a single photon of light
what are the main functions of the left hemisphere of the brain (5)
- control of segmental, sequential and logical ways of thinking
- contains the brocas area that coordinates the muscles for speaking and translates thought into speech
- contains the Wernicke’s area that stores the information involved in language comprehension
-interprets sensory stimulus received from the right side of the body - motor control of the right side of the body
whats the iris
the coloured muscle located at the front of the eye
what are sensory receptors
specialized cells or neuron endings that detect specific stimuli and sensory information
are there more rods or cones in the fovea centralis
cones
what forms the ciliary muscle and where does it attach
the choroid thickens and attaches to the lens
what does concave lens mean
the lens curves inwards
where are the ends of the stereocilia embedded
within the tectorial membrane
what are the two divisions of the nervous system
central nervous system and peripheral nervous system
how do rods transmit an impulse
when the rods absorb light, the rhodopsin splits into retinal and opsin which triggers a chain reaction and stops the release of the inhibitory neurotransmitter thus allowing the transmission of a neural impulse to the optic nerve
what is white matter composed of
myelinated axons
whats the common name for myopia
nearsightedness
what does the stapes (3rd ossicle bone) bone do
concentrates the vibrations into the oval window
what is grey matter composed of
cell bodies, dendrites and short unmyelinated axons
whats the aqueous humor
clear watery fluid located in the anterior chamber of the eye
what does the cornea do
portion of the eye where light enters; bends and directs the light rays that enter the eye in order to provide a stronger focus power on the retina
where must all sensory messages pass going t o the cerebrum pass through in order to be sensed consciously
the thalamus
what type of treatment can be used for nerve deafness
in some cases a device can be implanted in the ear to pick up sounds and directly relay signals to the auditory nerve
what does wernickes area do
stores the information involved in language comprehension
in general, what do sensory receptors do
convert one form of energy into an electrochemical energy which can be processed by the nervous system
wheres the anterior chamber located in the eye
in front of the lens
what dos convex lens mean
the lens curves outwards
what are the two main functions of the ear
balance and hearing
whats the typical treatment for conduction deafness
hearing aids to amplify sounds
example of photoreceptors
the rods and cones in the eyes that allow us to see different levels of light and shades of colour
how do you treat myopia (2)
- by wearing concave lenses that diverge incoming light rays so that the image falls directly on the retina
- corrective laser surgery that reshapes the cornea to focus light onto the retina
where do low frequencies stimulate
stimulate the hair cells farthest from the oval window
what are the 3 membranes that make up the meninges
pia mater, arachnoid, dura mater
what structure changes the size of the pupil
the iris
whats the common name for hyperopia
farsightedness
where is the midbrian located
found above the pons in the brainstem
whats adaptation
the process of the iris adjusting the size of the pupil based on the light conditions
whats nerve/sensorineural hearing loss
damage to the inner ear structures, hair cells or other hearing nerve damage
where do sympathetic nerves originate from
the middle of the spinal cord
what is the brain responsible for
sensation and perception, involuntary and voluntary motion, internal regulation, control of reproduction, adaptation, learning, intelligence, memory, consciousness, emotion
what do the cones do
- detect different wavelengths of light to give the eye ability to see and process different colors
- provide sharp acute vision
what does cerebrospinal fluid do
bathes the cells and cushions the brain as well as carries nutrients and removes waste
what do the semicircular canals and vestibule contain
sensors for balance
what is the hypothalamus primarily responsible for (7)
- producing oxytocin and ADH
- regulates the secretion of hormones from the pituitary gland
- control center for blood pressure, heart rate, body temperature, hunger, thirst, pleasure, sex drive and water balance
- regulates the body’s internal environment
- links the nervous system and endocrine system
- controls the automatic nervous system
- involved in certain aspects of behavior
after the optic nerve, how does the visual information get to the brain
information travels from the retina, through the optic nerve to the thalamus and then to the occipital love of the cerebral cortex
what does the pons do
passes information between the two regions of the cerebellum and between the cerebellum and the medulla oblongata
what is frequency and what are its units
the number of waves that pass through a specific point every second; measured in hertz (Hz)
whats constriction
when the pupils get smaller to restrict light flow
how many pairs of nerves go to the spinal cord
31
whats myopia
when someone can easily see close objects but cant see objects from far away
what do the suspensory ligaments do (3)
- support and maintain the eyeballs typical forward and upward position
- prevent any downward displacement of the eye
- holds the lens in place
what does the cerebellum do
- coordinates complex motor tasks by integrating sensory and motor information
- helps with balance and coordination
- unconscious coordination of posture, reflexes, body movements and fine voluntary motor skills
how do cones transmit and impulse
when the cones absorb specific wavelengths of light, the photopsin splits into retinal and opsin which triggers a chain reaction and stops the release of the inhibitory neurotransmitter thus allowing the transmission of a neural impulse to the optic nerve
whats sensory adaptation
when the brain filters out redundant, insignificant sensory informaiton
what are reflexes
when a sensory receptor senses pain/danger and sends a signal to the spinal cord which bipasses the brain and sends a response through the motor neuron to protect from danger
whats cerumen
earwax
whats the ciliary muscle
ring of smooth, involuntary muscle within the ciliary body of the eye
where does perception of pitch occur
in the brain
what attaches to the basilar membrane
the sensory mechanoreceptors called hair cells
what does the cochlea do (simple)
contains the structures that convert the mechanical energy of sound into electrical impulses that are transmitted to the brain
where is the brain located
in the cranial cavity
whats the function of the eustachian tube
to allow air pressure to equalize when there is a difference in air pressure between outside and inside the ear
what are the suspensory ligaments
the hammock-shaped thickening of the tissue that is located underneath the eye
how do you treat hyperopia
by wearing a convex lens that bends light rays at a sharper angle
what does the ciliary muscle do
allows the eye to focus on objects at different distances by adjusting the shape of the lens
how do the utricle and saccules work
the otoliths lie above the hair cells so when the head dip’s forward or back gravity pulls on the otoliths which puts pressure on some of the hair cells and causes them to send a neural impulse to the brain that indicates the position of the head
what divides the cerebrum into two hemispheres
longitudinal fissure
what are otoliths
calcium carbonate granules located in the saccule and utricle
what are the semicircular canals
3 fluid filled loops, where each loop is associated with a different dimension of space
what does brocas area do
coordinates the muscles for speaking and translates thought into speech
whats the pathway of nerve impulses from the ear to the brain
sensory neurons in the ear send information through the auditory nerve to the brain stem, thalamus and then the temporal lobes
what structure changes the shape of the lens
ciliary muscles
what shape does the lens form when its focusing on objects farther away and how
ciliary muscles relax, suspensory ligaments contract and the lens flattens
what does the iris do
regulates the amount of light that enters the eye by controlling the size of the pupil
what stimulates photoreceptors
light energy
what does the outer ear cnisist of
the pinna and auditory canal
what is the job of the middle ear ossicles
to conduct and amplify sound waves across the middle ear
what is consolidated during dleep
memory and learning
what does the optic nerve do
transmits sensory information received by the eye to the brain by carrying messages from the retinas photoreceptors to the brain
what is conductive hearing loss
damage to the sound conduction system of the outer or middle ear, preventing sounds from passing through
whats the optic nerve
the main nerve in the eye that extends from the retina, through the optic canal, out the back of each eye and connects directly to the brain
what happens to the stereocilia when there is repeated or sustained exposure to loud noise
the stereocilia are permanently destroyed
what do mechanoreceptors in the skin do
allow the body to detect light touch, pressure and pain
how do the photoreceptors in the eye (rods and cones) transmit an impulse
sensory neurons are attached to the rods and cones which come together to form the optic nerve. The photoreceptors are initially stimulated by light which causes the breaking down of the visual pigment which stimulates/initiates a nerve impulse in the attached sensory neurons based on the process of a typical neuron’s depolarization. These impulses travel through the fibers of the optic nerve that emerge from the back of the eye and are then transmitted to the occipital lobe of the brain
whats the cornea
the transparent portion of the sclera located at the front of the eye
where is the posterior chamber of the eye located
behind the lens
what does it mean to have binocular vision
when both eyes are used to collect visual information about an object, enabling the brain to perceive depth and 3D images
what happens when sound waves hit the tympanum
the tympanum vibrates and its vibrations are them passed on and amplifie by the ossicles
what are the main structures of the forebrain
cerebrum, hypothalamus, thalamus, pituitary gland
what structures are included in the middle ear
eustachian tube connects to the middle ear, the ossicles, bordered by one side of the tympanum
