Card Set Information
Avascular Tunic Layer Consists of?
a) Canal of schlemm
Vascular Tunic Layer Consists of?
Ciliary Process with ciliary muscle
Iris - Pupil
Neural Tunic Layer Consists of?
-Rodes & COnes
-Other Cells - bipolar neurons & ganglion cells
What does Anterior Cavity consist of?
What does posterior Cavity Consists of?
Photons move as waves of _____ and in _________ waves.
We can only see ___ - ___ nm wavelength of radiant energy.
400 - 750
What are the two functions that eyes carry out?
List Wavelength Longest to Shortest.
Where does the most refraction occur in eye?
Varriance of curve of the lens
Steps of accomodation:
Increase in parasympathetic stimulation
Contraction of ciliary muscles
Relaxation of suspensory ligmaents
Relaxation of lens
Lens becomes rounder
What do the eyes tranduce?
Convert electromagnetic spectrum into nerve impulses.
What refracts light and has an elastic capsule?
Where should the refracted light land in order to see clearly?
On the retina!
Consensual light reaction of iris casues....
: flash light pupil gets small
: bring fingertip close to eye
Closest distance at which you can focus on an image is called?
Near Point Accomodation
When light reach the retina....
the image is upside down.
Retinas Sesning of Photons Pathway
Horizontal cells inhibit ganglion cells
Structure of receptors include....
What does opsin determine?
What wavelength of light gets through
None found in...
None found in macula lutea with fovea centrails
Contains purple photo pigment called rhodopsin.
At rest they continuously make c-GMP which:
c-GMP stimulates cation chans to open + charge enters.
Only the receptor to be depolarized at rest
-Depolarization causes exocytosis of neurot
Rod Tranduction (of light energy to chemical signal) Pathway
*Light Must filter past Opsin
*Activates retinal.chromophere indisc memb
*Retinal Changes Shape
*Opsin binds to G-protein (transducin)
*Tranducin activates Phosphdesterase
*Enzyme Hydrolyzes c-GMP
*Decrease c-GMP levels in photoreceptor
*Close plasma mem. ion channels (ones controled by c_GMP)
*Na+ influx increases but K+ efflux continues
Rods can _____ to continuous stimulation and secrete _____ Instead of having an _____
______ are less sensitive to light than ______ which means needs more light to be activated.
Cones (Need more light to activate - Color)
Rods (Need less light - No color)
What are the 3 different types of photopigments that make 3 different types of cones?
WHere do photoreceptor synapse?
on bipolar neurons
Neural Pathway of Vision
Lateral Geniculate Nucleus
Fourth Order Neuron out optic radiation
Visual Association of occipital lobe
Lateral Geniculate Nucleus
Extrinsic Muscles Responsible for two types of movements:
Smooth pursuit movement
: Eyes dont jerk.
Saccadic Eye Movement
: Eyes Jerk!
P-Type Ganglion Cell
M-Type Ganglion Cell
What is the correct term for near sightedness?
Unable to see far objects because eyeball is too long.
Fixed with concave lens
Oculus Dexter (OD)
Means Right Eye
Oculus Sinister (OS)
Means Left Eye
Unable To see Near Objects clearly
Eyeball too short
Looking at things far away is not restful
Corrected with convex lens
Farsightedness caused by loss of elasticity of the lens of the eye, occurring typically in middle and old age.
a clouding of the lens of the eye causing difficulty in seeing.
Curvature of the cornea and lens is not perfectly symmetrical
An increase in intraocular pressure causes destruction of the retina from the outside in (tunnel vision first)
Forces optic nerve to push against eyes
Ea. Taste receptor reacts...
Special Epithelial Cells
* Have hairlike structures.
* Basal Cell divides and replaces the taste epithelial cells damaged.
* Food must be dissolved to enter taste pores
*Ea. Taste receptor reacts w/varying degrees to different chemicals
Where is taste triggered in the brain?
Pathway for sweet
Sugar -G-protein - Blocks K+ Chan. -Depolariza
Pathway for Sour
H+ enters cells
Block leaky K+ chans
Pathway for Salty Taste
Na+ Enters channels in membrane
Pathway for Bitter Taste
Alkaloids --> Stimulate G-Proteins
Pathway for Umami flavor
Affects a G-Protein
Taste projects to the ______ _____ near the mouth region of the _______ ____.
How long do olfactory epithelial cell live?
Each epithelial cell (afferent neuron) contains receptors for one specific _____
Epithelial Cells live for ~ 2months and have single enlarged dendrite
__% of flavor of food comes from smell.
We recognize _______ different odors using ~ ______ different protein receptors.
Women usually like/respond to Andro_____ but not _______
(sweat) Men usualy like/respond to ________
Copulines Sweat + Female Hormone
Information sent to Limbic System and Olfactory Cortex