The Eye, The Ear Flashcards
Which nerve provides after ent impulses for vision
Optic II
Which never provides motor control of eye and constricts iris
Oculomotor III
Which 2 nerves supplies eyeball movement and proprioception
Trochlear IV and Abducens VI
Which nerve controls lacrimal gland and tears
Facial VII
Lacrimal caruncle provides elevation at medial comminsure and contains
Oil and sweat glands
what percentage of sensory receptors are in the eye?
70%
TRUE or FALSE: half of the cerebral cortex is involved with processing balance and hearing
FALSE: it is involved with vision
Eyebrows prevent ??? from reaching the eye
perspiration.
Conjunctiva is a ??? that produces a ??? that lubricates the eye
transparent membrane, produces mucous secretion
bulbar conjunctiva lines which part of the eye, eyelids or white of the white of the eyes?
white of the eyes
what secretion is made of a dilute saline solution containing mucus, antibodies, and
lysozyme
tears
eyeball contains three layers, the fibrous, vascular and ???
sensory
fibrous layer of eyeball consists of connective tissue called the ??? and ???
sclera and cornea
does the sclera or cornea give eyeballs their shape?
sclera
does the sclera or cornea bend light as it enters the eye?
cornea
what helps make the cornea clear/ helps with clarity?
Sodium pumps of the corneal endothelium on
the inner face
the vascular layer of the eye consists of three layers, the iris, choroid and ???
ciliary body
which supplies blood to all regions of the eye, the choroid, iris or ciliary body?
choroid
what does the choroid region do to prevent visual confusion
absorbs light to prevent visual
confusion
what controls the lens shape?
ciliary body
TRUE or FALSE: Capillaries of ciliary processes secrete fluid
TRUE
what type of vision and light brightness causes sphincter papillae
(circular muscles) to contract; pupils constrict
close vision and bright light
what type of vision and light brightness causes dilator papillae (radial
muscles) to contract; pupils dilate
distant vision and dim light
is distant or close vision sympathetic response?
distant vision
is distant or close vision a parasympathetic response?
close vision
The sensory layer of the eye consists of ???
the retina
the retina is a delicate 2-layered membrane that absorbs ??? and prevents ??? and stores ???
light and prevents its
scattering and stores vitamin A
the neural layer of the retina is a ??? that transduces light energy
photoreceptor
TRUE or FALSE: the neural layer fo the retina contains bipolar cells, ganglion cells, amacrine
cells, and horizontal cells
TRUE these help with transmitting and processing signals
the optic nerve turns into ??? in the retina
ganglion cells
the rods in the eye operate in dim or bright light and provide indistinct, fuzzy, non-colour peripheral vision?
dim
the cones in the eye operate in dim or bright light and provide high-acuity colour vision?
bright
cones are concentrated in what part of the eye?
the fovea centralis and are found in the macula lutea
rods in the eye are more numerous at peripheral region of the retina, away from the ???
macula lutea
vitreous humour transmits ??? and holds the neural retina firmly against
transmits light and holds neural retina against pigmented layer
which humour supplies nutrients and oxygen mainly to the lens and
cornea but also to the retina, and removes wastes
aqueous humour
TRUE or FALSE: refraction is the Bending of a light ray due to change in speed when light passes from one transparent medium
to another
TRUE
does refraction need to occur for distant vision?
only a very small amount, as light rays from distant objects are nearly parallel at
the eye and eye basically at rest
for what type of vision must the eye make active adjustments?
close vision because light diverges at it gets closer to the eye
high resolution vision is due to non-converging pathways in rods or cones?
cones
what is the visual pigment of rods?
rhodopsin which is formed from vitamin A
rhodopsin breaks down when ???
light enters the eye and is absorbed
afferent impulses for hearing occurs in which part of what nerve?
the cochlear part of vestibulocochlear nerve
afferent impulses for sense of balance occur in which part of what nerve?
the vestubular branch of vestibulocochlear
what is the point of the auditory tube in the middle ear?
allows outside air in to equalise pressure
what resppnds to gravity and changes in the position of the head in the ear?
the vestibule
what is the vestibule?
it is a Central egg-shaped cavity of the bony labyrinth of semi circular canals
semicircular canal receptors respond to what type of motion
rotational movements of the head
where do sounds in the hearing range travel through?
through the cochlear duct, vibrating the basilar membrane at a specific location, according to the frequency of the sound
what resonates in response to high-frequency pressure waves in the cochlea?
short, stiff fibres that span the width of the basilar membrane near oval window
there is 1 row of inner hair cells
and 3 rows of outer hair cells in what part of the cochlea?
the spiral organ
maculae in the ear respond to which type of movement: rotation or linear acceleration forces?
linear acceleration forces
whereabouts can you find maculae that respond to vertical movement of head
saccule
whereabouts can you find maculae that respond to horizontal movements and tilting the head side to side?
the utricle
how is the crista ampularis activated?
Cristae respond to changes in velocity of
rotatory movements of the head
