Exam Two Flashcards
Receptor
any structure specialized to detect stimulus
Sense Organ
composed of never tissue and another tissue that enhances response to a certain type of stimulus
Transduction
conversion of one form of energy to another
Sensation
sensory signal that reaches the brain causes subjective awareness
4 types of receptor information
MILD
Modality
Intensity
Location
Duration
Modality
type of stimulus– vision, hearing, taste
identified by labeled nerve pathways
Sensory Adaption
becoming less aware to stimulus over time
Phasic Receptors
instant burst of action potentials followed by quick reduction, adapt quickly
Tonic Receptors
slow and steady nerve signals, adapt slowly
Exteroceptors
sense stimuli external to the body
ex: vision, hearing, taste , smell
Interoceptors
detect stimuli in the internal organs
ex: stomach, bladder, intestines
Proprioceptors
sense position and movement
ex: muscles, tendons, joints
General Senses (somatosensory)
receptors widely distributed in skin, muscles, tendons, joints
bare dendrites
ex: touch, pressure, stretch , temp
Special Senses
limited to the head and are innervated by the cranial nerve
complex
ex: vision, hearing, equilibrium, taste
Unencapsulated Nerve Endings
types?
sensory dendrites that are not wrapped in connective tissue
free nerve endings
tactile discs
hair receptors
Encapsulated Nerve Endings
types?
nerver fibers wrapped in glial cells or connective tissue
tactile corpuscles
end bulbs
lamellar corpuscles
bulbous corpuscles
Filiform Papillae
tiny spikes without taste buds, but sense texture
most abundant
Foliate Papillae
sides of the tongue , chewing occurs so most chemicals
degenerates 2-3yrs
Fungiform Papillae
mushroom, 3 taste buds
widely distributed, but tip and sides mostly
Vallate Papillae
V shape in the rear , surrounded by circular trench
7-12- 250 buds each
3 types of cells on taste buds
taste
supporting
basal
Salty
produced by metal ions such as sodium and potassium
Sweet
produced by organic compounds
associated with carbs and high caloric foods
Sour
acids H+, citrus fruits
Bitter
spoiled foods and alkaloids (nicotine, caffeine, and morphine)
Umami
“meaty”, savory
Taste Pathway
nucleus in medulla –hypothalamus and amygdala–thalamus
Smell Pathway
Olfactory fibers– tufted & mitral– glomeruli–Cerebral Cortex
Hearing
responce to vibrating air molecules
Equilibrium
sense of motion, body orientation, and balance
Sound
audible vibration of molecules
water solids or air
Pitch
sense of whether a sound is high or low
Loudness
perception of sound energy, intensity, or amplitude vibration
Parts of Outer Ear
Auricle
Auditory canal
Parts of Middle Ear
Tympanic Membrane Intrinsic muscle Auditory tube Auditory Ossicles Oval Window
Parts of Inner Ear
Vestibule
Spiral Organ
Cochlea
Modiolus
Progression of sound waves
enter auditory canal on one side and nerve signals exit the inner ear on other side
Conductive Deafness
interfere with the transmission of vibrations to the inner ear
Otosclerosis
fusion of auditory ossicles with each other, preventing bones from vibrating
Sensorineural Deafness
death of hair cells
long exposure to loud noises
Auditory Pathway
auditory tube– ear drum– ossicles– oval window– spiral organ
CNS– pons– midbrain– thalamus– temporal lobe
Static
perception of head when the body is stationary
Dyanamic
perception of motion or acceleration
Linear
change in velocity when going in a straight line
Angular
change in rate of rotation
responsible for static and dyanamic
Saccule and Utricle
5 ares receiving equilibrium info
Cerebellum Nuclei CN III,IV, VI Reticular Formation Spinal Cord Thalamus
Vision
perception of object in environment by means of light that they emit or reflect
Light
visible electromagnetic radiation
UV below 400nm
IR above 700nm
Accessory to Orbit
Eyebrow
Eyelids
Conjunctiva
Lacrimal Apparatus
Extrinsic Eye Muscles
RECTUS Superior Inferior Lateral Medial
OBLIQUE
Superior
Inferior
Components of Outer Fibrous Layer
Sclera
Cornea
Components of Vascular Layer
Choroid
Ciliary body
Iris
Components of Inner Layer
Retina
Beginning of optic nerve
Optical Components
Cornea
Aqueous Humor
Lens
Vitreous Body
Neural Components
Retina
Optic nerve
Cataract
clouding of lens
Glaucoma
Elevated pressure within eye
Emmetropia
eye is relaxed and focused on an object more then 6m away
3 steps for close range vision
Convergence of the eyes
Constriction of the pupil
Accommodation of the lens
Visual Pathway
bipolar cells– ganglion cells– optic nerve– thalamus– primary visual cortex in occipital lobe
