HP CHP16

Sensory Receptor

Any structure specialized to detect a stimulus.

What is deeper insight 16.1 about?

Middle-ear infections causing inflammation

What is deeper insight 16.2 about?

Deafness

What is deeper insight 16.3 about?

Common causes of blindness

What is the difference between receptors?

Some receptors are simply nerve endings, while others are specialized cells that are adjacent to afferent neurons

What is the function of sensory receptors?

to convert a stimulus into electrical signals.

What is the name of the sensory receptors process?

Transduction

How are local potentials generated?

when a stimulus is received

What happens after local potential that cause the transmission of action potentials along the afferent neurons?

the sensory cell is not attached to the LP ; it would trigger the neurotransmitters

What is another name for local potential?

Receptor potentials

Is local potential the same thing as receptor potential?

Yes

What are the four types of information that are transmitted by sensory receptors?

Modality. location, intensity, and duration

What does the modality information encoded?

stimulation of the hearing, vision, taste, and touch; determined where the sensory signals end in the brain

What does the location information encoded?

encoded by which nerve fibers carry signals to the brain

What does the intensity information encoded?

encoded in a couple of ways:

• a) the number of action potentials per unit time can increase

• b) greater numbers of neurons may be stimulated

What does the duration information encoded?

encoded by how long the stimulation last

What is sensory adaptation?

when the firing of neurons persists, eventually getting used to the neurons firing.

What is the difference between tonic receptors and phasic receptors?

Phasic receptors adapt quickly, while tonic receptors adapt slowly

How are receptors categorized according to stimulus modality?

receptors are categorized by; thermoreceptors, photoreceptors, nociceptors, chemoreceptors, an d mechanoreceptors

How are receptors categorized according to distribution of receptors?

Receptors are classified according to the distribution if they are general sensor receptors and special sense receptors.

General Sensor receptors

receptors in the skin, muscles, tendons, joints and viscera

Special Sense Receptors

limited to receptors in the head including vision, hearing, and equilibrium

What are the special receptors involved in proprioception (muscle spindles and
tendon organs)

mechanoreceptors

What is gustation (tastants)?

A chemical sense that stimulates sensory cells clustered in about 4,000 taste buds.

What are papillae?

The bumps on the tongue.

What are the four kinds of papillae?

Filiform papillae, foliate, papillae, fungiform papillae, vallate papillae

Which one of the four kinds of papillae contains taste buds?

foliate papillae, fungiform papillae, and vallate papillae

What is the structure of taste receptors?

soft palates, tonsils, pharynx, and epiglottis, and modified elongated epithelial cells

What is the functions of taste receptors?

to transmit taste signals to your brain

What are the five different taste specializations?

• Salty

• Sweet

• Umami

• Sour

• Bitter

what kinds of substances/compounds actually trigger salty taste buds

metal ions like sodium and potassium

what kinds of substances/compounds actually trigger sweet taste buds

organic compounds, especially sugar

what kinds of substances/compounds actually trigger umami taste buds

a “meaty” taste stimulated by certain amino acids

what kinds of substances/compounds actually trigger sour taste buds

associate with H+ ions for acids, such as vinegar or citrus fruits

what kinds of substances/compounds actually trigger bitter taste buds

associate with spoiled foods and alkaloids or poison such as nicotine and caffeine

What is olfaction

the response to airborne chemicals

What does odorants do?

to detect odors dissolved in the mucous

Where is olfactory mucosa located?

in the roof of the nasal cavity

What does olfactory mucosa contains?

bowman’s glands and nerves

Know the structure of olfactory cells?

Their axons join together to make up the fascicles

What is the name for the foramina by which the fascicles leave the nasal cavity

cribriform foramina

How many different kinds of olfactory receptors are present?

10

What happens when an odorant binds to a receptor to cause a receptor potential?

triggers action potential in the axon of the olfactory cell, then signals are transmitted to the brain.

Definition of Hearing

a response to vibrating air molecules

Definition of Sound

an audible vibration of molecules

What is pitch?

the sense of whether a sound is high or low

Which components of sound waves is related to pitch?

Hertz (Hz)

How is pitch measured?

Frequency and Hertz (Hz)

What is loudness?

the perception of sound intensity, which is a function of amplitude of vibration.

Which components of sound waves relate to loudness?

decibels (dB)

What is the functions of pinna

It directs sound into the auditory canal

what is included in the structure anatomy of the inner ear?

the vestibule, which contains organs of
equilibrium and the cochlea.

What is the functions of auditory canal

helps to amplify the sound.

What is the functions of guard hairs

protect the rest of the pelage from abrasion and frequently from moisture

What is the functions of tympanic cavity

holds the malleus, incus and stapes

Another name for the tympathic membrane?

Eardrum

What is the functions of auditory tube (Eustachian tube)

drains and aerates (introduces air into) the middle ear.

What is the functions of malleus

transmit vibrations from the eardrum to the inner ear

What is the functions of incus

transmits vibrations from the malleus to the stapes

What is the functions of stapes

transmits sound vibrations from the incus to the oval window

What is the functions of oval window

movement of fluid within the cochlea and activation of receptors for hearing

What is the functions of inner ear

detect sound and head motion to begin the processes of hearing and balance control

What is the functions of vestibule

to perceive movement and acceleration, so that the body may maintain equilibrium and balance

What is the functions of cochlea

receiving and analyzing the sounds which are interpreted by hair cells or stereocilia.

How is earwax created

The ear canal is lined with hair follicles and glands that produce a waxy oil

Which glands create earwax

ceruminous glands

What is the function of earwax

the function is to protect, pelage and moisturize.

What is the structure of cochlea?

a coiled labyrinth, like a snail, Scala vestibula, Scala tympani, and the cochlear duct

What liquids are found in the scala tympani/ scala vestibuli

perilymph

What liquids are found in the cochlear duct

endolymph

What makes up the spiral organ

composed of hair cells, which have long, stiff stereocilia on their apical surface.

Wat is the importance of the spiral organ

the importance is to converts vibrations into nerve impulses

What is the structure of hair cells?

Each hair have 50 stereocilia, arranged from short to tall

What is the relationship between hair cells and the tectorial membrane?

Each upward movement of the basilar membrane pushes the inner hair cells closer to the stationary tectorial membrane.

What is the importance of the mechanically-gated ion channels ions channels and tip links?

Each of the stereocilia on the inner hair cells has a single transmembrane protein at its tip that acts as a mechanically-gated ion channel.

What is the importance of the tip linking

Tip linking connects the tips of the stereocilia.

How does the vibrations at the oval window lead to movements of the basilar membrane

Sound waves cause the oval window base to move, which then causes the basilar membrane to be displaced and starts a traveling wave that sweeps from the base toward the apex of the cochlea

tthe vibrations of the oval window leads to bending of what?

the stereocilia of the inner hair cells and the opening of the channels so that the hair cells are depolarized?

Equilibrium

The sense of body orientation, movement, and balance

What is the names of the two vestibules chambers

saccule and utricle

What is the structure of vestibule

semicircular ducts, 2 chambers: saccule and utricle

Static equilibrium ; which part of the vestibule is associated with it

the perception of the orientation

Dynamic equilibrium ; which part of the vestibule is associated with it

the perception of motion and acceleration

Linear acceleration; which part of the vestibule is associated with it

both saccule and utricle

Angular acceleration; which part of the vestibule is associated with it

semicircular ducts

The structure of both the saccule and the utricle

contains a patch of hair cells and supporting cells called a
macula.

the structure of the macula

vestibule nerves, hair cells, supporting cells, otoliths, otolith membrane

How are the shapes of the hair cells altered in response to motion.

when we move our head, the jelly moves which causes the hair cells to bend in different direction, which leads to the creation of electrical signals.

The structure of the semicircular ducts

ampullae, semicircular ducts: anterior, lateral, posterior

the structure of the ampulla

crista ampullaris

How is the vestibulocochlear nerve formed

The cochlear nerve and the vestibular nerve come together

Vision

the perception of objects by lights they emit or reflect

What is the wavelengths of light that are visible to humans.

400nm-700nm

What is the amount of ultraviolet radiation humans can see

less than 400 nm>

What is the amount of infrared radiation humans can see

<above 700nm

What is the accessory structures function

protect, lubricate and support the eyeball.

What is the accessory structures structure?

orbit, eyebrows, eyelids, lacrimal apparatus, and extraocular muscles.

What is the names of the three layers in the eyes?

tunica fibrosa, tunica vasculosa, tunica interna

What is the structure of the names of three layers in

tunica fibrous: sclera (white outer layer) and cornea (modified sclera that is transparent)
tunica vasculosa: choroid (highly vascularized, deeply pigmented layer behind the retina), ciliary body (secretes aqueous amor, holds the lens in place with suspensory ligaments, focuses the lens) , iris (an adjustible diaphragm that controls the diameter of the pupil)
tunica interna: retina

What is the optical components

cornea, aqueous humor, lens, vitreous humor