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