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