Smartbook Chapter 16: Nervous System
Which are the functions of the inner ear?
- balance - hearing
The spiral organ rests on the ______.
basilar membrane
Olfactory receptor cells are ______ neurons.
bipolar
The optic disc contains ______ photoreceptors.
no
Gustatory cells are ______.
chemoreceptors
In phototransduction, the __________ responds to light stimulation by changing its resting membrane potential, resulting in a change in the neurotransmitter it releases.
photoreceptor
Each type of photoreceptor has both an outer segment that extends into the ________ layer of the retina and an inner segment.
pigment
Where is the trans-retinal transported so that the retinal can be reconverted back to its cis formation?
pigment epithelium
The dissociation of _________ into its two components is called the bleaching reaction.
rhodopsin
Which are true of rods?
- There are more than 100 million rod cells per eye. - They function well in dim light.
Vestibular nerve axons project first to which structures?
- cerebellum - medulla oblongata
Which events occur during bright light adaptation?
- cones gradually adjust - rods become inactive - pupils constrict
Nerve signals arriving at the superior olivary nucleus are involved in which functions?
- decreasing the vibration of the sound - turning our head toward the sound - localizing the sound
what would stimulate somatic nociceptors?
- exposure to acid on skin - sprained ankle - touching a hot pan
Each macula of the utricle and saccule is composed of which structures?
- hair cells - supporting cells
Which are true of conjunctiva?
- it contains goblet cells - it is vascular - it does not cover the cornea
Sensory receptors in which structures help monitor and adjust our equilibrium?
- saccule - utricle - semicircular ducts
Which structures are part of the vestibular complex?
- semicircular ducts - saccule - utricle
The utricle and saccule are involved in functions involving the position of the head?
- static equilibrium - linear acceleration
Which are muscles located in the middle ear?
- tensor tympani - stapedius
Optic tracts extend to which structures after they leave the optic chiasm?
- the lateral geniculate nucleus of the thalamus - superior colliculi
What are the functions of the auditory ossicles?
- transmit sounds waves to inner ear - amplify sound
Gustatory cells have a ______ lifespan.
7 - 10 days
Olfactory glands are also known as ______ glands.
Bowman
Axons of olfactory cells form fascicles of cranial nerve number ______.
CN I
The optic disc is associated with ______.
CN II
Which are true of the olfactory hairs?
They are unmyelinated, they are immobile
When hair cells in the spiral organ are distorted, they initiate a nerve signal in cranial nerve ____________.
VIII
Refraction of light for vision is greatest as light rays pass from ______ into the ______ because the difference in their refractive index is maximal.
air ; cornea
The semicircular ducts are involved in detecting _______ acceleration.
angular
Which cavity of the eyeball is divided into an anterior and posterior chamber?
anterior cavity
Both the anterior and posterior chambers of the anterior cavity contain _______ humor.
aqueous
The lamina propria is made of ______ tissue.
areolar connective tissue
Sound waves are funneled into the ear by the ______.
auricle
When the ___________ membrane moves, the ___________ on the spiral organ hair cells distort because they are anchored by the tectorial membrane.
basilar ; stereocilia
During the dark current, the ______ cells are inhibited, so the brain does not perceive light.
bipolar
In the light, __________ cells are no longer inhibited and therefore release the neurotransmitter glutamate.
bipolar
When light stimulates the photoreceptors, the _________ cells become depolarized and release the neurotransmitter ___________ .
bipolar ; glutamate
The process is called the bleaching reaction because rhodopsin goes from a ______ color to ______.
bluish-purple , colorless
Which is a type of tonic receptor that detects both continuous deep pressure and distortion of the skin?
bulbous corpuscles
receptors initiate sensory input to the _____.
central nervous system
Aqueous humor is secreted by the ______.
ciliary processes
What is the name of the "snail-shaped" structure of the inner ear?
cochlea
The auditory sensory axons of the ______ branch of cranial nerve number _______ terminate in the cochlear nucleus within the brainstem.
cochlear ; 8
As we adjust to low light, our ______ becomes nonfunctional and it may take ______ for rhodopsin to become regenerated sufficiently so that you can see well in low-light conditions.
cones ; 20-30 minutes
The sphincter pupillae ______ the pupil.
constricts
the receptors for the special senses are found w/ in the _______.
cranium
When you go from a bright light environment to a dark environment, you have a slow sensitivity to low light levels. This is called _________ ________ .
dark adaptation
When elevated levels of cGMP are present, Na+ channels in the photoreceptor membrane are kept open and Na+ enters the photoreceptor. This is called the _______ ________ .
dark current
Free nerve endings are terminal branches of ______.
dendrites
Light rays are refracted or bent when they pass through two media of different ______.
densities
Photoreceptors are ________ when it is completely dark.
depolarized
Photoreceptors
detect changes in light intensity, color, and movement
Baroreceptors
detect changes in pressure
Thermoreceptors
detect changes in temperature
Which is an accessory structure of the eye?
eyebrow
True or false: The regeneration of rhodopsin is slow; typically only half of the bleached rhodopsin is regenerated after about 1 minute.
false - About half of the rhodopsin is regenerated in about 5 minutes.
The outmost layer of the eye is called the ______ tunic.
fibrous
The short and spiky papillae that are on the anterior two-thirds of the tongue are ______ papillae.
filiform
The lens is ______ when we are viewing faraway objects.
flattened
Which are the types of papillae?
foliate, vallate, filiform, and fungiform
When the bipolar cells release their neurotransmitter, the ______ cells propagate a nerve signal along the ________ nerve.
ganglion or ganglia ; optic
pain is an example of a ________ sense.
general
What disease causes fluid build up in the eye, dislocating the lens?
glaucoma
Which may result in symptoms such as reduced field of vision, dim vision, and/or halos around lights?
glaucoma
As a consequence of the dark current, ______ channels in the photoreceptor open.
glutamate
When rhodopsin is split by light stimulation, the calcium and sodium channels are also closed and this blocks the release of the neurotransmitter called _________ .
glutamate
In a taste bud, the basal cells replace the _____ cells.
gustatory
Sensory receptors in the utricle detect the position of the ______.
head
The term equilibrium refers to our awareness and monitoring of our ______- position.
head
The vestibulocochlear nerve transmits ______ information.
hearing and equilibrium
Endolymph has a ______ potassium concentration.
high
Light causes the photoreceptor plasma membranes to ______.
hyperpolarize
Rods are essentially nonfunctional in bright light because ______.
in bright light, rhodopsin will bleach as fast as it is reformed
Some of the axons from the cochlea project directly to the ________ colliculus of the midbrain.
inferior
Nerve signals arriving at the ______ are relayed to skeletal muscles that cause us to jump and turn our head in response to loud sounds.
inferior colliculi
When the photoreceptors stop __________ the bipolar cells, the bipolar cells can then release their neurotransmitter that binds to receptors on the ganglion cells.
inhibiting or blocking
The segment of each photoreceptor that contains organelles for the cell such as mitochondria is the _______ segment.
inner
The segment of the photoreceptors that connects directly to the cell body is the ________ segment.
inner
Cranial nerve VIII innervates the ______.
inner ear
Perilymph is similar to ______ and endolymph is similar to ______.
interstitial fluid ; intracellular fluid
What structure is the dividing line between the anterior and posterior chambers?
iris
The majority of the optic tract axons extend to the thalamus, specifically to the ______.
lateral geniculate nucleus
The process by which your eyes adjust from low light to bright light conditions is ______ ________.
light adaptation
The sensory epithelium of the utricle and saccule forms a covering on a small, raised oval area called the ________ .
macula
tactile receptors are a type of _____?
mechanoreceptor
Accommodation is the process of making the lens ______.
more spherical
The vibration of the tympanic membrane causes ______.
movement of the ossicles
A detached retina is more likely to occur if a person is ______.
nearsighted
Optic tracts ultimately are directed to the primary visual cortex in the ______ lobe.
occipital
Olfactory hairs house receptor proteins for detecting ______ specific odorant molecule(s).
one
Ganglion axons of the retina converge to form the ________ nerve.
optic
Place the structures of CN II in order from anterior to posterior.
optic nerve, optic chiasm, optic tract
The utricle and saccule contain small crystals. What are these crystals called?
otoliths
The segment of each photoreceptor that is composed of hundreds of discs containing photopigments that are capable of absorbing light energy is the ________ segment.
outer
A detached retina is caused by a separation between which two layers?
outer pigmented and inner neural layers
Small elevations that can be easily seen on the tongue surface are called ______.
papillae
Free nerve endings are usually found in the ______.
papillary layer of the dermis
Accommodation is controlled by the ______ division of the nervous system.
parasympathetic
If stimulated over a period of time, ________ receptors lose sensitivity over time. (eventually sensitivity)
phasic / adapting (16.1c)
The regeneration of _______ , in cones, occurs much more quickly than the regeneration of __________ in rods; therefore, cone cells are not as negatively affected by bright light as rods.
photopsin , rhodopsin
The process by which photoreceptors become activated when the photopigments are altered by light entering the eye is ______.
phototransduction
the area that a receptor cell gathers information from is called the ________.
receptive field
______ occurs when impulses from an organ are perceived as originating from the skin.
referred pain
Light rays are ______ when they pass through the lens and the cornea.
refracted or bent
Root hair plexuses are usually found in the ______.
reticular layer of the dermis
Specialized free nerve endings that surround hair follicles are called _________ hair plexuses.
root
The lens is ______ when we are viewing close-up objects.
rounded
The vestibule contains two structures, the utricle, and ______.
saccule
The vestibule contains two structures, the utricle, and _______.
saccule
Which chamber is most superior?
scala vestibuli
What structure makes up the posterior 5/6 of the fibrous tunic?
sclera
When a figure skater does a lengthy spin on the ice, it is the sensory receptors in her ________ canals of the inner ear that are informing her brain about the position of her moving head.
semicircular
Equilibrium
sense of balance
audition
sense of hearing
vision
sense of sight
Olfaction
sense of smell
Gustation
sense of taste
receptors for general senses are usually______.
simple in structure
Receptors for general senses are distributed throughout the ______ and viscera.
skin
localization + sensitivity are easily determined in a _____ receptive field.
small
At the optic chiasm, ______ of the axons from each optic nerve cross to the opposite side of the brain.
some
Which are basic taste sensations?
sour, sweet, umami
Which auditory ossicle contacts the oval window?
stapes
Axons from the optic tract project to the ______ colliculi.
superior
Reflexive movements of the head, eyes, and neck are coordinated by the ______.
superior colliculi
In a hearing, secondary neurons can go one of two pathways; they can go directly to the inferior colliculus or go to the ________ ________ nucleus before they go to the inferior colliculus.
superior olivary
What type of phasic receptors detects light touch, shapes, textures?
tactile corpuscles
A flattened dendritic disc is a type of unencapsulated receptor called a ______.
tactile disc
What is the most numerous type of receptor?
tactile receptors
Which membrane is gelatinous?
tectorial membrane
The inner ear is located in the ______ bone.
temporal
What lobe of the brain processes auditory information?
temporal lobe
a feature common to all receptors is ______.
the ability to respond to a stimulus
somatic receptors are found w/ in ______.
the body wall
Taste buds are found on the tongue and ______.
tongue and soft palate
Neurons in the olfactory bulb travel through the olfactory _______ to the brain.
tract, or glomeruli
Upon exposure to light, the retinal straightens out and reconfigures into a form called -retinal.
trans
True or false: In cones, the bleaching reaction occurs as cis-retinal transforms to trans-retinal.
true
True or false: It is the utricle and saccule that inform your brain that your head is upright.
true
True or false: Unlike other sensory information, olfactory pathways do not project to the thalamus.
true
Which taste sensation translates as "delicious flavor" and is perceived as a meaty flavor?
umami
The roof of the cochlear duct is formed by the __________ membrane.
vestibular
When the stereocilia of the maculae or the crista ampullaris distort, nerve signals are initiated through the ______ branch of the vestibulocochlear nerve (CN VIII).
vestibular
Hearing and our sense of balance comes from the stimulation of which cranial nerve?
vestibulocochlear
The two types of nociceptors are somatic nociceptors and _____ nociceptors
visceral
stretch receptors in the stomach would be classified as what type?
visceral sensory
The fovea centralis lies ______ the macula lutea.
within
What color is the macula lutea?
yellow
Prior to being stimulated by light, the retinal portion of rhodopsin is in a bent twisted shape called -retinal.
cis
The cis-retinal, in the process of regeneration, is transported back to the __________ where it associates with the opsin and reforms the ______________ .
rod ; rhodopsin
Chemoreceptors
detect chemicals
Nociceptors
detect tissue damage and pain