118 terms

lab 26- 35 bio lab practical

Normal vision
What are the light rays refracted by?
By the lens and cornea then to the photoreceptors of the retina.
Defect of the curvature of the cornea or the lens.
What do concave lens fix?
Concave lens separate the light rays(divergence.) So the concave lens fix eyes that are nearsightedness. The lens of concave eyes create a "u" formation.
What do convex lens fix?
Convex lens cross the light rays (convergence). So the convex lens fix eyes that are farsightedness. The lens of the convex eyes form a round bowl protruding out.
Why does farsightedness (hyperopia) occurs?
When someone is farsightedness the image is focused behind the retina because the eyeball is too short.
Due to natural aging process, what does this cause lens to do?
The lens' elasticity decreases, which causes people to slowly not have the ability to see nearby or closeup objects.
Hereditary defects in color vision result from lack of what?
Certain cones needed to absorb certain wavelengths of light.
What is the purpose of visual acuity test? And what is used for testing?
To test the sharpness of vision. A chart called, Snellen Eye Chart is used.
What is the consequence of an astigmatism?
Some of the portions of an image projected on the retina are sharply focused, but other parts are blurred.
What is the astigmatism testing? What is used?
The test is testing if an individual has an astigmatism, testing if there is a defect in the curvature in the cornea or the lens.
the process by which the eye's lens changes shape to focus near or far objects on the retina.
What is the accommodation testing?
Testing the elasticity of the eye. The accommodation involves a reflex which involves the muscles of the ciliary body. Relaxing the tension of the suspensory ligaments that are attached to the lens. this causes the surface to become convex.
Normal accommodation for people around the age of 20 is what?
10 cm of points
What does the color vision test? What is used?
Test if the person was born lacking cones causing to be sensitive to reds or greens. The Ishihara's book is used to test any red-green defects.
protanopia colorblindness
possess decreased sensitivity to the red-sensitive cones
deuteranopia colorblindess
possess decreased sensitivity to green-sensiive cones
What is blind-spot demonstration?
Demonstrating that proves that the optic nerve does not possess any photoreceptors.
Name and define the three reflexes: Photopupillary reflex, accommodation pupillary reflex, and convergence reflex.
photopupillary reflex= smooth muscles controlling the size of the pupil.
accommodation pupillary reflex= pupil constricts as a normal accommodation reflex to focus on close objects.
convergence reflex= eyes converge as normal convergence reflex to focus on close objects.
Posterior 5/6 this of middle (vascular) tunic
choroid coat
white part of outer (fibrous) tunic
Transparent anterior portion of outer tunic
inner lining of eyelid
secretes tears
lacrimal gland
fills posterior cavity of eye
vitreous humor
area where optic nerve exits the eye
optic disc
smooth muscle that controls light entering the eye
fills anterior and posterior chambers of the anterior cavity of the eye
aqueous humor
contains visual receptors called rods and cones
connects lens to ciliary body
suspensory ligament
cause lens to change shape
ciliary muscles
List the structures and fluids through which light passes as it travels from the cornea to the retina.
CORNEA, aqueous humor, PUPIL OF IRIS, lens, VITREOUS HUMOR, retina
How are the rods and cones different?
Rods= dimlight (night time) & black/white colors & more of rods than cones
Cones= bright light & see color
what kind of tissues do you think is responsible for this quality of toughness that cause cutting a layer of the eye difficult?
dense fibers of C.T.
where do you find aqueous humor in the dissected eye?
behind cornea and lens
what is the function of the dark pigment in the choroid coat?
dark pigment absorbs all the excess light
Where is conjunctiva located?
Located outside the cornea
The eye contains what, modified neurons located on its inner wall.
Name in order the labeling of the lacrimal apparatus.
lacrimal gland, superior and inferior canaliculi, lacrimal sac, nasolacrimal duct, nasal cavity, and inferior nasal concha
jellylike mass helps to hold the lens in place anteriorly and helps to hold the retina against the chord coat.
vitreous humor
serves to reflect light back throughout the retina, an action thought to aid the night vision of some animals. its located on an iridescent area of the choroid coat beneath the retina.
tapetum fibrosum
The organs of static equilibrium are located within two expanded chambers called the what and the saccule.
all of the balance organs are located within the blank bone of the skull.
the receptor cells of these organs are found in the wall of the membranous labyrinth in a structure called the blank.
otoliths are small grains of composed of
calcium carbonate
sensory impulses travel from the organs of equilibrium to the brain on the blank nerve.
vestibulocochlear nerve
the sensory organ of a semicircular canal lies within a swilling of the clean called the what
the sensory organ within the ampulla of a semicircular canal is called a what?
crista ampullaris
the blank of this sensory organ consists of a dome-shaped gelatinous mass.
when the head is moved, the fluid inside the membranous portion of a semicircular canal tends to remain stationary because of the blank of the fluid.
parts of the what of the brain interpret impulses from the equilibrium receptors.
When the eyes are open what sensory organs provide information needed to maintain equilibrium?
Within the utricle and saccule of the vestibules of the inner ear.
When the eyes are open what sensory organs provide information needed to maintain equilibrium?
within the ampullae of the semicircular canals of the inner ear
aka of static equilibrium
gravitational equilibrium
aka of dynamic equilibrium
rotational equilibrium
auditory ossicle attached to tympanic membrane
air-filled space containing auditory ossicles
tympanic cavity
contacts hairs of hearing receptors
tectorial membrane
leads from oval window to apex of cochlea
scala vestibuli
s-shaped tube leading to tympanic membrane
external acoustic meatus
wax-secreting structure
ceruminous gland
cone-shaped, semitransparent membrane attached to membrane
tympanic membrane (ear drum)
auditory ossicle attached to oval window
contains endolymph
membranous labyrinth
bony canal of inner ear in temporal bone
osseous (bony) labyrinth
connects middle ear and pharynx
auditory tube
extends from apex of cochlea to round window
scala tympani
Where are hearing receptors located?
Located in the organ of corti within the inner ear
Where does the auditory impulse pass over to?
vestibulocochlear nerve into the auditory cortex of the brain.
what parts of the inner ear have the function of equilibrium
semicircular canals, utricle and saccule of vestibule
What test is use to detect if there is sensory deafness.
weber test
tast receptor cells are modified
epithelial cells
the opening to taste bud is called a
taste pore
the blank of a taste cells are its sensitive part.
taste hair
before the taste of a substance can be detected, the substance must be dissolved in
saliva or water
bitter taste are associated with
salt receptors are mainly stimulated by ionized inorganic
substances that stimulate taste cells bind with
receptor sites on the surface of taste hairs.
the olfactory interpreting centers are located deep within the temporal lobes and at the base of the blank lobes of the cerebrum
a chemical would be considered blank if a person lacks a particular receptor site on the cilia of the olfactory neurons.
olfactory bulbs lie on either side of the
crista galli of the ethmoid bone
the axons of olfactory receptors pass through small openings in the blank of the ethmoid bone.
cribiform plate
distal ends of the olfactory neurons are covered with hairlike blank
Olfactory, or smell receptors are blank neuron surrounded by columnar epithelial cells.
bipolar neurons
umami sensation is associated with
aspartic and glutamic acids
structure formed by the crossing over of optic nerves
optic chiasma
part of diencephalon that forms lower walls and floor of third ventricle
cone-shaped structure attached to upper posterior portion of diencephalon
pineal gland
connects cerebral hemispheres
corpus callosum
ridge on surface of cerebrum
separates frontal and parietal lobes
central sulcus
parto of brainstem between diencephalon and pons
rounded bulge on underside of brainstem
a layer of dura mater that separates cerebellar hemispheres
falx cerebelli
cerebral lobe located deep within lateral sulcus
thin layer of gray matter on surface of cerebrum
cerebral cortex
trigeminal nerve
stimulates superior oblique eye muscle
abducens nerve
lateral eye movement
optic nerve
vision and opening eyes
oculomotor nerve
pupil constriction and open eye lid, moving eyes
hypoglossal nerve
control tongue movements
are routes followed by nerve impulses as they pass through the nervous system
nerve pathway
interneurons in a withdrawal reflex are located in the
spinal cord
are automatic subconscious responses to external or internal stimuli
the effector muscle of patellar reflex
quadricep femoris
the normal plantar reflex results in
flexion of toes
stroking the sole of the foot in infants results in dorsflexion and toes that spread apart, called the
bobinski reflex
sensory receptors of a withdrawal reflex are located in the
effectors of a reflex are glands and
band of pia mater that anchors dura mater to cord
denticulate ligament
channel though which venous blood flow
dural sinus
separates dura mater from bone of vertebra
epidural space
contains cerebrospinal fluid
subarachnoid space
ascending tract to the brain to interpret touch, pressure and body movements
lateral spinothalamic
descending tract whose fibers conduct motor impulses to sweat glands and muscles to control tone
descending tract whose fibers conduct motor impulses to skeletal muscles
ascending tract to the cerebellum necessary for coordination of skeletal muscles
posterior spinocerebellar
ascending tract to the brain to give rise to sensations of temperature and pain
fasciculus gracilis