Special Sense Organ Flashcards
Senses
divided into special senses and general senses
Special Sense
senses that have localized sense organ
Vision
- organ: eye
- occibital lobe
- optic nerve(2)
Hearing
- organ: ear
- temporal lobe
- vestibular cochlear nerve(8)
Equilibrium
- organ:ear
- cerebellum
- vestibular cochlear nerve(8)
Taste
- organ:tongue
- gustation nerve
Smell
- organ:nose
- temporal lobe
- olfaction nerve(1)
General Senses
-receptors that are scattered/ distributed throughout the body
Cutaneous
- located at or near the surface of the body
- provide information about the external environment
- ex. touch,pressure,temp,pain
Internal Organ Receptors
- located in blood vessels and internal organ
- provide information about the internal environment
Proprioceptor
- located in musles tendon joints
- provide information about body position and movement
The EYE
- receptors for visual stimuli
- system for bending light rays(refractive apparatus)
- lacrimal apparatus
- accessory muscles
- nervel supply
- nerve supply
Coats of the eyeball
- eyeball sits in orbit
- wall is made of layers
- layers are called coats or tonic
- layers are different in front vs. the back
- overmost coat=fibrous tunic
Outer Coat
-Sclera(back): tough connect tissue, white due to collagen, avascular
- Cornea(front): transparent, avascular, bulges forword slightly
- cornea is part of the refractive apparatus
MIddle Coat(Vascuar Layer)
- Choroid-connective tissue and blood vessels, contains dark brown pigment
- dark brown pigment prevents scattering/reflecting off the light inside the eye
Ciliary Body(muscle)
- holds the lens in place, controls the shape of the lens (accommodation)
- the lens is the only part of the refractive apparatus that can change
Lens
- biconvex, adjustable part of the refraction system bi-convex=bulges out on both sides
- only adjustable part of the refraction system
- lens is clear
- thickness of the lens can be adjusted
- adjustment in thickness gives accomadation
Iris(muscle)
- colored
- made up of 2 sets of muscle fibers
- 2 set of muscle fibers control size of pupil
Pupil
pupil is an opening in the lens
- controls amount of light that eneters the eye
- in bright light pupil constricts
- in dark light the pupil dilates
Inner coat
retina: 2nd tunic, nervous tunic
- somplex structure that lines the back 2/3rd of the eye
- contains photoreceptors(visual receptos)
- rods detect the presense of light
- cones detect color
- optic disc
Rods
- detect light
- found in edges of the retina
- responsibe for night vision