A&P - Senses

sensory receptors

collect information from the environment, and relay it to the brain

Perception

a person's view of the stimulus

Chemoreceptors

respond to changes in chemical concentrations (smell, taste)

nocioreceptors (pain)

respond to tissue damage

Thermoreceptors

respond to changes in temperature

Mechanoreceptors

respond to changes in pressure and movement of fluid

Photoreceptors

respond to light energy (in eyes only)

sensory adaptation

diminished sensitivity as a consequence of constant stimulation (not in nocioreceptors)

outer ear

auricle, auditory canal, and tympanic membrane

typanic membrane

eardrum

middle ear

tympanic cavity, auditory ossicles, eustachian tubes

auditory ossicles

malleus, incus, stapes

inner ear

semicircular canals and cochlea

purpose of semicircular canals

Aids in maintaining balance when head rotates with use of fluids

purpose of cochlea

hearing

Hearing

sound waves get funneled down the auricle and through the auditory canal, the sound waves vibrate the tympanic membrane, vibrates the auditory ossicles, vibrations travel through the cochlea, vibrates the hair of the organ of corti, the message is transmitted to the brain from the nerve that's connected to the cochlea

static equilibrium

the perception of the orientation of the head when the body is stationary, detected by the macula

dynamic equilibrium

the perception of the orientation when the head and body are moving, detected by the crista ampulla

Eye accessory organs

Eyelids

Eyelashes

Lacrimal Gland (makes tears)

Lacrimal Duct (drains tears)

parts of the eyeball

sclera, cornea, optic nerve, iris, pupil, lens, vitreous humor, aqueous humor

Retina cells

rods: peripheral and night vision

cones: color vision

myopia

nearsightedness (distant objects blurry); focus light in front of retina

hyperopia

farsightedness (near objects blurry); focus light beyond the retina

astigmatism

Blurred vision, resulting from unequal curvatures of the lens or cornea

Cataracts

clouding of the lens

Glaucoma

Blocked drainage of aqueous humor (increases pressure)

Smell

nasal cavity is lined with mucous membranes that have smell receptors connected to the olfactory bulb which sends sensations to the brain, sense molecules in vapor, 7 sensations

Taste

taste buds throughout mouth detect 5 tastes (sweet, sour, bitter, salty, umami) are attached to nerves that send sensations to the brain

Touch

many different touch receptors are located in the skin. (heat, cold, pain, light touch, hair movement, and strong pressure)

Sight

Light is bent by the cornea before being bent by the lens and focus on the fovea of the retina on the back of the eye. The pupil is made smaller or larger by the iris tightening or losing.