Anaphy
to detect changes in the external or internal environment to enable the body to respond appropriately to maintain homeostasis
purpose of sensations
pathway of impulses for a sensation
sensory pathway
detect a change and generate impulses
receptors
transmit impulses from receptors to the cns
sensory neurons
white matter in the cns
sensory tracts
feels and interprets the sensations
sensory area
presentation seems to come from the area where the receptors were stimulated even though it is the brain that's truly feels the sensation
projection
the degree to which a sensation is felt
intensity
the effect of a previous or simultaneous sensations on a current sensation as the brain compares them
contrast
becoming an aware of a continuing stimulus
adaptation
presentation remains in the consciousness after the stimulus has stop
after image
provide information about the external environment and the skin itself
cutaneous senses
receptors for pain, itch, heat and cold
free nerve endings
receptors for touch and pressure
encapsulated nerve ending
is biselar pain that is felt as cutaneous pain
referred pain
knowing where our muscles are without looking at them
muscle senses
muscle detect stretching
stretch receptor
uses unconscious muscles sense to coordinate voluntary movement
cerebellum
are in taste buds on the tongue
chemoreceptors
are in upper nasal cavities that detect vaporize chemicals
chemoreceptors
detect changes in gi hormones and nutrient levels in blood
receptors for hunger
detect changes in body water
osmoreceptors
produces tears
lacrimal glands
tears wash the anterior eyeball and contain ________ inhibit bacterial growth
lysozyme
outermost layer of the eyeball, the first light refracting structure
sclera
middle layer of eyeball; dark blue pigment absorbs light to prevent glare within the eyeball
choroid layer
change shape of lens which is made of transparent elastic protein and which refracts light
ciliary body and suspensory ligament
two sets of smooth muscle fibers regulate diameter of pupil that is how much light strikes in the retina
iris
innermost layer of the eyeball contains rod
retina
detect light, abundant toward periphery of retina
rods
detect color, abundant in center of retina
cones
contains only cones, area of best color vision
fovea
no rods or cones, optic nerve passes through eyeball
optic disc
contains vitreous humor that keeps the retina in place
posterior cavity
contains aqueous humor that nourishes the lens and cornea
anterior cavity
relaxes for distant vision, muscle contracts for near vision
ciliary muscle
breaks down to scotopsin and retinal and an electric impulse is generated
in cones specific wavelengths of light are absorbed
rodopsin
permitting binocular vision
optic chiasma
branches to the midbrain for visual reflexes
optic tracts
auricle or pinna has no real function for people
outer ear
eardrum at the end of ear canal vibrates when sound waves strikes
middle ear
transmit vibrations to inner ear at oval window
auditory bones
extends from middle ear to nasopharynx, allows air in and out of middle ear
eustachian tube
lined with membranous labyrinth
inner ear
is fluid between bone and membrane
perilymph
is fluid between membrane
endolymph
contains receptors for hearing, hair cells in the organ of corti
cochlea
sound waves stimulate vibration of eardrum
physiology of hearing
impulses are interpreted as position of the head at rest
utricle and succule
impulses are interpreted as movement of the body, changing speed, stopping or starting
semicircular canal
detect changes in blood
arterial receptors
curves over top of heart, it's body contains chemoreceptors
aortic arch
detect changes in blood pressure
pressoreceptors
detect changes in ph are oxygen and carbon dioxide levels in the blood
chemoreceptors