Senses - Chapter 19 Flashcards
Another word for sensory information
stimuli
sensation refers to as what?
conscious awareness to stimuli
What are the 2 classes of receptors?
general sense receptors and special sense receptors
What do general sense receptors detect?
temperature, pain, youch, stretch, and pressure
What do special sense receptors detect?
gustation, olfaction, vision, equilibrium, and audition
Where are general sense receptors housed?
throughout skin and organs
Where are special sense receptors housed?
in complex organs in the head
What are the 3 criteria used to describe receptors?
stimulus origin, receptor distribution, and modality of stimulus
Area through which the sensitive ends of a receptor cell are distributed is referred to as what?
receptive fields
Describe the receptor of smaller receptive fields
more sensitive and precise the receptor is to the location and nature of the stimulus
What is gustation?
sense of taste
Gustatory cells are known as what?
taste buds
Where are taste buds located?
on the dorsal surface of the tongue in papillae
Elevated epithelial and connective tissues located on the dorsal surface of the tongue are called what?
papillae
What are the 4 types of papillae?
filiform, fungiform, valiate, and foliate
What are taste buds composed of?
numerous cells called gustatory cells, which are enclosed in supporting cells
Each gustatory cell has a dendritic ending called a what?
gustatory microvilli or taste hair
Taste hairs are activated by what in the oral cavity?
taste molecules
Taste buds from the anterior 2/3 of tongue conduct gustatory information through which cranial nerve?
CN VII (facial nerve)
Taste buds from the posterior 1/3 of tongue conduct gustatory information through which cranial nerve?
CN IX (glossopharyngeal)
Olfaction is what?
sense of smell
What olfactory epithelium consists of what 3 cell types?
olfactory receptor cells, supporting cells, basal cells
Where are olfactory hairs located?
at the apical end of the olfactory receptor cells, are free nerve endings
olfactory bulb neurons project axon bundles called what?
olfactory tracts
Where are the photoreceptors for vision located?
inside the eye
photoreceptors detect what?
light, color, and movement
What does the conjunctiva contain?
goblet cells to lubricate and moisten eyes
Conjunctiva is located where?
lines anterior surface of eye and inner surface of eyelid
What is the function of eyebrows?
prevent sweat from dripping into the eye
What is the function of eyelashes?
prevent large foreign objects from contacting the eyes
What are the eyelids (palpebrae)?
moveable anterior [rotective covering of the eye
What is the function of tarsal glands (meibomian gland)?
contain sebaceous glands to prevent tear overflow and the eyelids from sticking together
Where are the tarsal glands located?
located within both eyelids
What is the papillary fissure?
opening between the 2 eyelids
What are the medial and lateral commissures?
where eyelids unite at their medial and lateral borders
small reddish structure at medial commissure is called what?
lacrimal caruncle
What does the lacrimal caruncle contain?
modified sweat glands
What is the function of the lacrimal apparatus?
produce, collect, and drain lacrimal fluid (tears) from the eye
What is the function of tears?
to lubricate anterior surface of the eye to help prevent bacterial infections
Tears contain antibiotic-like enzymes called what?
lysozyme
What are the 4 components of the lacrimal apparatus?
- lacrimal caruncle
- lacrimal puncta
- lacrimal canaliculus
- nasolacrimal duct
What does the lacrimal caruncle contain?
modified sweat glands
What is lacrimal puncta?
small holes in the caruncle
What is the function of the lacrimal canaliculus?
drain lacrimal fluid into lacrimal sac
What is the function of the nasolacrimal duct?
receive tears from lacrimal sac and drain fluid into nasal cavity
What are the 3 principal layers of the eye?
- fibrous tunic
- vascular tunic
- retina
What fibrous tunic is composed of what 2 components?
cornea and sclera
What are the 3 regions that the vascular tunic is composed of?
- choroid, ciliary body, iris
What is the function of the choroid?
maintains vast network of capillaries
What is the ciliary body composed of?
ciliary muscles and ciliary processes
Suspensory ligaments from ciliary body attach to what structure of the eye?
lens
Contraction or relaxation of the ciliary muscles changes the shape of the lens and results in what?
focus of incoming light onto the retina
What Iris contains 2 muscles, what are they?
sphincter pupillae muscles and dilator pupillae muscles
Sphincter pupillae muscles are controlled by which division of the ANS?
parasympathetic system
The sphincter pupillae muscles cause the pupil to do what?
contract
Dilator pupillae muscles are controlled by which division of the ANS?
sympathetic system
What dilator pupillae muscles cause the pupil to do what?
dilate
The retina is composed of what 2 layers?
pigmented layer and neural layer
The pigmented layer is attached to what?
the choroid
What does the pigmented layer do?
absorb light that passes through the retina and provide photoreceptors with vitamin A
What does the neural layer house?
photoreceptors
What are the 3 layers of the neural later?
photoreceptor layer, bipolar cells, and ganglion cells
Which neural layer is the deepest layer?
photoreceptor layer
Which neural layer is the most superficial?
ganglion cell layer
The “blind spot” on the retina is what?
optic disc
Where is the optic disc located?
where ganglion cell axon exits retina to form optic nerve (CN II) and retinal arteries and veins enter and exit the reina
The optic nerves lack what?
photoreceptors
The fovea centralis is also known as the what?
central vision
The fovea centralis contains what?
highest proportion of cones and almost no rods
What is the function of cones?
detect different colors
What is the function of rods?
detect lower levels of lights - require less energy
Tension of ligaments attached to lens cause the lens to do what?
change shape
Where is the anterior cavity located?
between the lens and cornea
The anterior cavity is filled with that?
aqueous humor
The aqueous humor drains into space called the what?
scleral venous sinus
Where is the posterior cavity located?
posterior to lens and anterior to retina
What posterior cavity is filled with what?
vitreous humor
The organs of equilibrium and hearing are contained where?
the ear
What are the 3 anatomical regions of the ear?
external, middle, and inner ear
The skin-covered, funnel-shaped, elastic cartilage structure in the inner ear is called the what?
auricle
The auricle leads to a bony tube called the what?
external acoustic meatus
What is another name for the tympanic membrane?
eardrum
What is cerumen?
wax-like secretion from the glands in external acoustic meatus
What does the middle ear contain?
opening to the auditory tube
What are the names of the 3 auditory ossicles?
Malleus (hammer), Incus (Anvil), Stapes (Stirrup)
Which auditory ossicle is attached to the tympanic membrane?
malleus
Where is the inner ear located?
spaces within the petrous portion of the temporal bone
what is the bony labyrinth?
space in the inner ear
The fluid-filled tubes in the bony labyrinth are called the what?
membraneous labyrinth
What is housed in the membraneous labyrinth?
receptors for equilibrium
What is the perilymph?
the space between the walls of the bony labyrinth and is filled with fluid similar to CSF
The fluid that fills the membraneous labyrinth is called what?
endolymph
What are the 3 regions of the bony labyrinth?
vestibule, semicircular canals, and cochlea
The vestibular complex is composed of which 2 canals?
vestibule and semicircular canal
What are the 2 sac-like membraneous labyrinth parts of the vestibule?
the utricle and saccule
Membranous labyrinth within the semicurcular canal
semicircular ducts
The cochlea houses a membraneous labyrinth called the what?
cochlear duct
The maculae structure is located where?
along the internal walls of the utricle and saccule
On the apical surface of the maculae structure, the stiff microvilli are called?
sternocilia
What is the long cilium on the apical sure of the maculae structure called?
kinocilium
What is the position of the kinocilium and sternocilia when it translates electrical activity to the brain?
bent position
