Chapter 10: The Senses
Which of these conditions are correct for viewing objects at a distance.
Flatter lens Suspensory ligaments under tension
What are otoliths?
Grains (crystals) of calcium carbonate
What is the name of the protective outer layer covering the posterior five-sixths of the eye?
Sclera
The optic disc is also known as the _____ _____ , as it lacks photoreceptors.
blind spot
What is the function of the ciliary muscles?
change tension of suspensory ligaments
Which three components comprise the middle layer of the eye?
choroid ciliary body iris
The _____ is the pigmented layer found in the posterior five-sixths of the eye. It is very vascular, and helps nourish surrounding tissues. Its dark color helps keep the interior of the eye dark.
choroid coat
What is the name for the portion of the middle (vascular) layer that is located in the posterior part of the eye?
choroid coat
The middle layer of the eye includes the choroid coat, the _____ body and the _____.
ciliary body
In bright light, the _____ set of contractile cells of the iris will contract, causing the pupil to ______ in diameter.
circular; decrease
The wavelength transduced by some or all of the cones determines the _____ that is perceived by the brain.
color
The fovea centralis is the area of sharpest vision because it contains only ______ which do not have converging fibers.
cones
The nerve fibers from these photoreceptors converge less, hence they provide sharper images.
cones
Which type of photoreceptor has three types of opsins and, therefore, three types of pigments?
cones
The mucous membrane found lining the eyelids and covering the anterior surface of the eyeball (except the cornea) is called the _____
conjunctiva
The anterior part of the outer layer of the eye, called the _____ , is transparent and functions to focus light rays entering the eye.
cornea
The anterior chamber is located between the _____ and the _____ .
cornea iris
Which of these pigments are found tin cones?
cyanolabe chlorolabe erythrolabe
The area of the retina lacking photoreceptors and referred to as the "blind spot" is the optic _____
disc
The three semicircular canals are the location of the receptors for the sense of _____ equilibrium.
dynamic
Indicate three visual accessory organs of the eye.
eyelids extrinsic muscles lacrimal apparatus
The _____ and _____apparatus are visual accessory organs which protect the eye.
eyelids ; lacrimal
True or false: The lens is a rigid, flat, transparent structure located behind the pupil.
false
The region of the eye with the sharpest vision is called the _____ centralis, and lacks rods.
fovea
At the back of the retina is a slightly depressed area that produces the sharpest vision, contained within a yellowish region. What is this depression at the back of the retina called?
fovea centralis
Name the structure that control the size of the pupil and, thus, the amount of light coming into the eye.
iris
Name the structure that divides the anterior cavity of the eye into anterior chamber and posterior chamber.
iris
The _____ is a muscular diaphragm that constitutes the colored part of the eye and determines the amount of light entering the eye.
iris
The size of the pupil is determined by the _____
iris
The eye is moistened by secretions from the _____ gland.
lacrimal
The _____ is a transparent, elastic structure; its shape is modified by ciliary muscles.
lens
Name the structures found within the saccule and utricle that are associated with static equilibrium.
maculae
The vascular layer of the eye is the ____ layer.
middle
Fibers from the _____ half of each retina cross over to the other side of the brain at a structure called the optic chiasma.
nasal (medial)
After passing through the optic nerves, fibers from the nasal (medial) half of each retina cross over to the other side of the brain at a structure called the _______.
optic chiasma
The gelatinous material of the maculae are weighted by the presence of ______ within the gel.
otoliths
Match each layer of the wall of the eye with its description.
outer layer : fibrous layer inner layer : nervous layer middle layer : vascular layer
Receptors for _____ can be stimulated by different types of stimuli such as mechanical damage, extreme changes in temperature, chemical stimulation, or ischemia (disrupted blood flow).
pain
Tissue damage causes the release of various compounds which, in turn, stimulate _____ receptors.
pain
Rods and cones contain light-sensitive _____ that decompose when they absorb light energy, an example of which is rhodopsin.
pigments
At rest, the hair cells involved in hearing are _______.
polarized
Found within the ciliary body are two structures: the ciliary _____ and ciliary _____
processes muscles
The circular opening in the center of the iris is the ______
pupil
Light passes through the opening called the _____ to enter the posterior cavity of the eye. The diameter of this opening is regulated by the ____.
pupil; iris
The _____ set of muscle dilates the pupil.
radial
The _____ is the inner layer of the eye, containing the visual receptors.
retina
The inner layer of the eye is the _____.
retina
The light-sensitive biochemical in rods is called _____
rhodopsin
Photoreceptors called _____ are lacking in the fovea centralis thereby allowing sharp color vision at that point of the retina.
rods
Providing visual images in dim light (typically general outlines of objects) is the function of which type of photoreceptor?
rods
What type of photoreceptor is more sensitive to light and can, therefore, provide vision in dim light?
rods
What type of photoreceptor provides black/white/gray vision?
rods
Of the photoreceptors, the _____ are more sensitive to light than the _____ and therefore can provide vision in dim light.
rods cones
The "white" of the eye, forming the posterior portion of the fibrous (outer) tunic, is called the _____
sclera
The receptors for the sense of dynamic equilibrium are housed in what portion of the bony labyrinth?
semicircular canals
The sense of _____ equilibrium helps to maintain stability and posture when the head and body are still.
static
Name the structures that attach the lens to the ciliary body.
suspensory ligaments
The delicate fibers called _____ _____ , extend inward from the ciliary processes and hold the lens in position.
suspensory ligaments
Match each chemical with the type of taste sensation it generates.
table salt : salty caffeine : bitter sugar : sweet amino acids/meat : umami lemon : sour
Yhe organs for the sense of taste are called _____.
taste buds
Auditory pathways pass into the _____ lobes of the cerebrum.
temporal
Nerve impulses (signals) from the cochlea enter the auditory pathway, then enter the auditory cortices of the ______ lobes of the cerebrum.
temporal
The bony (osseous) labyrinth is located in which cranial bone?
temporal
The lens becomes more round when ____.
tension on the suspensory ligaments is decreased
The bony chamber between the semicircular canals and the cochlea is the _____
vestibule
The ______ of incoming light rays determines which type of cone is stimulated and the color that is perceived by the brain.
wavelength
What is the stimulus for triggering impulses associated with dynamic equilibrium?
Bending of cupula and hairs of hair cells
What is accommodation?
Changing of lens shape in order to change focus
What structure is the thickest part of the middle (vascular) layer of the eye?
Ciliary body
How is the shape of the lens changed, allowing a change in focus (near objects versus far objects)?
Ciliary muscles change tension of suspensory ligaments
List three functions of secretions produced by the lacrimal glands.
Contain enzyme that kills bacteria, reducing the risk of infection Lubricate the eye surface and lining of the lids Moisten the eye surface and lining of the lids
Which is correct for a large pupil diameter?
Contraction of pupillary dilator muscles.
What are the sensory organs for the sense of dynamic equilibrium?
Cristae ampullaris
What is sensory adaptation?
Ability of brain to become less responsive to some stimuli
Describe the receptor proteins on any one taste cell.
All the receptors on a taste cell detect the same taste sensation
How is the brain able to interpret whether an incoming sensation is touch vs. sound vs. vision?
Based on the region of the brain that receives the impulses
What happens to the tympanic membrane when sound waves pass down the external acoustic meatus?
The tympanic membrane vibrates.
Describe sensory adaptation by taste receptors.
They adapt quickly
_______ nerve ending receptors are the simplest receptors and are located between epithelial cells.
free
The _____ line principle explains why rubbing your eyes results in "flashes" of light being perceived.
labeled
The three auditory ossicles are the _____, the _____, and the _____
malleus incus stapes
The sensory impulses from taste receptor cells travel on fibers of several cranial nerves into the _____ _____ of the brain stem.
medulla oblongata
The _____ labyrinth is a tube that lies within a cavity called the _____ labyrinth.
membranous osseous / bony
The _____ ear is an air-filled space that houses the three auditory ossicles.
middle
The auditory tube connects the _____ ear and the nasal cavity.
middle
The auditory ossicles are located within the:
middle ear
Each olfactory receptor cell has _____ type(s) of receptor protein(s). Each type of receptor protein can bind ____ type(s) of odorant molecule(s). Any one odorant molecule can bind to ____ type(s) of receptor protein(s). Thus, we can detect many thousands of odors.
one; many; many
Match each class of receptor with its type of stimulus.
pain receptors: tissue damage photoreceptors: light energy chemoreceptors: specific molecules thermoreceptors: heat/cold mechanoreceptors: pressure and movement
Free nerve endings, tactile corpuscles, and lamellated corpuscles are receptors for what senses?
pressure
Sensory ______ is a process by which a person can pinpoint the region of stimulation (the origin of sensory impulses).
projection
Upon receiving sensory input, the brain causes the feeling to seem to come from the originating receptors. This process is called _____ , allowing a person to perceive the region of stimulation.
projection
The term ______ pain describes the sensation of visceral pain coming from a part of the body other than the part being stimulated.
referred
Food such as chili peppers can stimulate these receptors:
warm pain chemoreceptors
Place in order the sequence of a taste nerve pathway.
1. taste receptors are stimulated 2. cranial nerves carry sensory impulses 3. impulses are carried to the brainstem 4. impulses are then carried to the thalamus 5. impulses are then carried to the gustatory cortex
Sensory receptors for the sense of pain are widely distributed. However, they are lacking in what tissue?
Brain tissue
Where are the olfactory organs located?
Covering superior nasal conchae and part of nasal septum
What is the necessary condition for normal hearing to occur?
Equal air pressure on both sides of the tympanic membrane
What type of pain fiber is myelinated, and is associated with immediate sensation of sharp pain?
Fast pain fibers
What is the structure of the receptors that detect temperature?
Free nerve endings
______ are the simplest touch receptors, located between epithelial cells.
Free nerve endings
Indicate three types of touch and pressure receptors.
Free nerve endings Tactile (Meissner's) corpuscles Lamellated (Pacinian) corpuscles
________ corpuscles are found typically in the connective tissue capsule of synovial joints.
Lamellated or Pacinian
Referred pain associated with the heart is felt in what area of the body?
Left arm
What are the characteristics of fast pain fibers?
Myelinated, with fast conduction of impulses
Along with glutamate, the nociceptors release the neurotransmitter substance _______
P
What is referred pain?
Pain from one body region feels like it is coming from another body region
______ occurs when the brain becomes aware of sensory impulses; ______ occurs when the brain interprets those sensory impulses.
Sensation; perception
Describe the olfactory bulbs.
Site of synapses between olfactory receptors cells and cells of olfactory tract
Which type of pain fiber is associated with dull, aching sensation of pain, primarily due to the unmyelinated structure of the pain fibers?
Slow pain fibers
Which two the following senses use chemoreceptors?
Smell Taste
List the special senses.
Smell, taste, hearing, equilibrium, sight
Name the structure that contains the hearing receptors in the cochlea.
Spiral organ
The classification of sensory receptors as photoreceptors, thermoreceptors, etc., is based on what characteristic of the receptors?
Stimulus type that causes response
Name the encapsulated receptors for light touch which are abundant in hairless portions of the skin.
Tactile (Meissner's) corpuscles
Which three of the following regions are associated with receptors for the general senses?
Viscera Muscles Joints
The ability of the nervous system to become less responsive to a maintained stimulus is called
adaptation
Taste receptors undergo _____ very quickly.
adaptation / sensory adaptation
The ear is the organ that functions in the sense of hearing. It also functions in the sense of _____
balance / equilibirum
Olfactory receptors and taste receptors are examples of _______.
chemoreceptors
The _____ is the part of inner ear which functions in hearing.
cochlea
The part of the inner ear that functions in hearing is the _____
cochlea
What is the location of the auditory tube?
connects the tympanic cavity to the nasopharynx
Odorants are airborne, but olfactory receptors require that these molecules become _____ for detection.
dissolved
In order to be detected by olfactory receptors, odorant molecules must be _____.
dissolved in watery fluid
The sense of _____ equilibrium aids in maintaining balance when there is sudden movement or rotation of the head and body.
dynamic
Warm and cold receptors in the skin are _____.
free nerve endings
The ______ senses have receptors widely distributed throughout the skin and deeper tissues, and are structurally simple.
general
The _____ senses include touch, pressure, temperature, and pain.
general / exteroreceptive
The two major categories of sensory receptors are those for the _____ senses and for the _____ senses.
general ; special
Receptor cells involved in hearing are also called _____ cells.
hair
Name the receptor cells for the sense of hearing.
hair cells
There are several _____ olfactory receptors, and _____ of detectable odors.
hundred, thousands
As a person moves from a high altitude to a lower one, air pressure on the outside of the tympanic membrane ______. This change in pressure can affect hearing.
increases
The sensation of warmth or cold begins to fade within _____ of continuous stimulation.
minutes
Both the sense of taste and the sense of smell require that:
molecules be dissolved in order to bind to receptors and to be sensed
The hair cells involved in hearing release ______ in order to stimulate the dendrites of nearby sensory neurons.
neurotransmitter
Pain receptors are also called ______
nociceptors
Olfactory receptor proteins are stimulated by chemicals called _____ molecules
odorant
Taste cells usually respond to ____ taste sensation(s).
one
The conscious awareness of stimuli is _____.
perception
The _____ _____ provide the fluid in which chemical (food) molecules must dissolve in order for them to be tasted.
salivary glands
What part of the ear provides a sense of equilibrium?
semicircular canals
List two pain-relieving substances released by the brain.
serotonin enkephalins
Pain fibers that are unmyelinated and thin are classified as _____ pain fibers. Impulses carried by these fibers result in the sensation of a dull pain felt deep in tissues.
slow or C
The _____ organ (organ of Corti) contains the hearing receptors in the cochlea.
spiral
The _______ corpuscles respond light touch.
tactile
Which of the following are considered general senses?
touch temperature pain
True or false: Chemicals in some foods may stimulate pain receptors.
true
The five primary taste sensations are: sweet, sour, salty, bitter and _____
umami
In what part of the inner ear are the organs of static equilibrium located?
vestibule
Within the cochlea, different _______ respond to different sound frequencies (pitches).
hair cells
The ______ senses have specialized receptors and are confined to structures in the head such as the eyes and ears.
special
True or false: Receptors for the general senses are very localized, and found in the skin only.
false
True or false: Temperatures below 40 degrees C (113 degrees F) will stimulate pain receptors.
false
True or false: The auditory ossicles increase the force of vibrations from the oval window to the eardrum (tympanic membrane).
false
Masses of sensory epithelium on the nasal cavity and superior nasal conchae are the _____ organs.
olfactory
Odorant molecules stimulating a distinct set of receptor cells result in generation of _____ impulses.
olfactory
Within the olfactory organs, bipolar neurons are surrounded by columnar epithelial cells. These bipolar neurons are called _________.
olfactory receptor cells
The function of the auditory _____ is to amplify sound waves from the tympanic membrane to the oval window of the middle ear.
ossicles
The middle ear houses the three auditory _____ which include the malleus, the incus, and the stapes.
ossicles / bones
The three sections of the ear are: _____ ear, _____ear and _____ ear.
outer middle inner
The auditory ossicles convey vibrations from the tympanic membrane to the _____ which, in turn, leads into the inner ear.
oval window
The _____ senses are smell, taste, hearing/equilibrium and sight.
special
True or false: Temperature below 50 degrees F (10 degrees C) may produce a freezing sensation.
true
True or false: Warm and cold receptors undergo the process of sensory adaptation.
true
Sound waves that enter the external acoustic meatus with cause the _____ membrane to vibrate back and forth, reproducing the vibrations of the sound-wave source.
tympanic
The auditory ossicles convey vibrations from the _____ to the oval window which, in turn, leads into the inner ear.
tympanic membrane
Place the following events in the correct order, describing how dynamic equilibrium works.
1. rapid movement of head also moves semicircular canals 2. endolymph, which isnt moving with the head movement, bends the cupula 3. hairs embedded in cupula are caused to bend 4. associated sensory neurons are stimulation, sending impulses to the brain
There are _____ extrinsic muscles that move the eye in various directions.
6
Which two statements describe the functioning of the six extrinsic muscles of the eye?
Any given eye movement may utilize more than one extrinsic muscle Each extrinsic muscle causes one primary action
What sense is associated with the crista ampullaris?
Dynamic equilibrium
How does the ear differentiate between sounds of different frequencies (pitches)?
Hair cells at different locations in cochlea respond to different pitches.
Describe the choroid coat.
Highly vascular and darkly pigmented layer
Where is the conjunctiva found?
Lining eyelids and covering anterior eyeball (except the cornea)
Which describe rods?
Vision in dim light. More sensitive to light.
Action of the ciliary muscles alters the shape of the lens when focusing. This process is called _____
accommodation
Unlike in rods which all contain the same rhodopsin pigment, there are _____ different types of opsin proteins present in cones.
three
What is the cornea?
transparent part of outer (fibrous) layer of the eye
True or false: The area of the retina that produces the sharpest vision is fovea centralis.
true
The maculae, located in the ________ of the inner ear, are associated with the sense of ______ equilibrium.
utricle and saccule; static
