Anatomy Lab 3

Sense

A system that consists of a sensory cell type (or group of cell types) that respond to a specific kind of physical energy and that correspond to a defined region

Adaptation

process where sensory system becomes insensitive to a continuing source of stimulation.

nociceptors

sensory receptors that respond to pain stimuli, including thermal, mechanical, and chemical changes.

Vision

ability to detect electromagnetic energy, human range is from approximately 380 to 750 nanometers in wavelength.

sclera

the white outer layer of the eyeball, providing structural support and protection.

cornea

the transparent front part of the eye that covers the iris and pupil, allowing light to enter and helping to focus images.

outer epithelial sheet of the cornea

continually produces new cornea cells.

inner epithelial cornea cells

actively pumps sodium out of cornea thus keeping water content low

choroid

highly vascular and pigmented to absorb light and prevent reflection within the eye.

ciliary body

a structure that contains the ciliary muscle, which controls the shape of the lens for focusing.

aqueous humor

the clear fluid produced by the ciliary body, filling the space between the cornea and lens, providing nutrients and maintaining intraocular pressure.

vitreous humor

a clear gel-like substance filling the space between the lens and the retina, helping to maintain the eye's shape by creating pressure, providing support to the retina.

scleral venous sinus

where the aqueous humor drains from the eye

glaucoma

when aqueous humor doesn’t drain adequately and pressure increases in the eye

irises

only contain brown pigment

retina

innermost layer of the eye

pigmented epithelium

outermost layer of the retina, prevents light from scattering in the eye.

detached retina

occurs when neural components of the retina release from the pigmented layer, often caused by blow to the head

cataracts

hardening and clouding over the eye

lacrimal caruncle

in the median corner of the eye, produces secretions to help lubricate and protect the eye

sty

inflammation of one of the smaller glands

chalazion

infection tarsal gland

conjunctivitis

inflammation of the conjunctiva

pinkeye conjunctivitis

inflammation caused by bacteria or viral infection

nasolacrimal duct

where lacrimal secretions drain through to the nose

diplopia

double vision

strabismus

cross eyed, the affected eye rotates medially or laterally

accommodation of the lens

process that changes the lens from default flat to a bulged configuration for viewing close objects

parasympathetic, sympathetic

what fibers control close vision, what fibers control distant vision

cone cells

responsible for color differation, primarily found in the fovea

rod cells

responsible for contrast resolution

optic disc (blind spot)

where nerves and blood vessels enter and exit devoid of receptors

glial cells (muller cells)

funnels light to the rods and cones

pigmented epithelium

controls fluid and nutrient environment of photoreceptor region of the retina

rhodopsin

pigment that supplies us with blueish grey vision in shades of grey based on intensity of stimulation

phototransduction

light energy converted to a graded receptor potential

glutamate

released from bipolar cells, inhibits cell from releasing neurotransmitter to the ganglion cell

light adaptation

when moving from dark to light area, the intense light breaks down a massive amount of photopigments, brains interprets it as glare

optic chiasm

where fibers cross from each eye to the other side of the brain

saccadic masking

during rapid movement, brain selectively blocks visual processing

protanomaly, protanopia

some altered sensitivity in the red cone function, complete red cone deficiency

deutanomaly, deutanopia

some altered sensitivity in the green cone function, complete green cone deficiency

tritanopia

complete blue cone deficiency (there’s no altered sensitivity on blue cones)

myopia

short-sightedness

hyperopia

long-sightedness

presbyopia

inability to focus on near objects with aging

astigmatism

blurred vision due to differences in the curvatures of the cornea or lens at various locations

tympanic membrane

when sound vibrates this membrane, the vibration is transferred to the malleus, incus, and stapes

pharyngotympanic tube

connects the middle ear to the nasopharynx so pressure is equal in ear

otitis media

middle ear inflammation

organ of Corti

receptor organ for hearing, housed in the cochlea

fast motility

as outer hair cells depolarize and hyperpolarize, they contract and stretch

equilibrioception

the perception of balance and is related to the vestibular system in the inner ear

maculae

within the saccule and utricle, responds to changes in head position (linear acceleration) and the pull of gravity

semicircular canals

filled with endolymph, detects rotary movements of the head

crista ampullaris

contains a gelatinous, wedge-shaped structure that blocks the ampulla and prevents flow of the endolymph

vestibular nystagmus

describes strange eye movement that occurs reflexively in response to events

motion sickness

brain receives sensory mismatch, eyes send info that person is in a relative constant position, vestibular system send info that the body is significantly moving

conduction deafness

something decreases the ability of sound to conduct to the fluid of the inner ear

otosclerosis

bony overgrowth, fusion of the middle ear bones together, or fusion of the stapes to the oval window

tinnitus

symptom of buzzing, ringing, or clicking in ears without an actual auditory stimulation

Meniere’s syndrome

affects all aspects of the inner ear, caused by buildup of fluid in the inner ear

fast pain

carried from injured tissue by myelinated A-delta fibers, sharp pain

slow pain

dull aching after initial pain, is delivered to cns by unmyelinated C fibers

thermoception

sense of heat and cold (absence of heat)

proprioception

perception of body position

tapetum lucidum

layer of tissue in eyes of animals, not present in humans