Upload
michal-wozniczka
View
220
Download
0
Embed Size (px)
Citation preview
8/8/2019 Eyeball Project
1/13
-THE-
8/8/2019 Eyeball Project
2/13
A SYSTEM IS A COLLECTION OF
OBJECTS THAT WOULD BECOMPLETELY IRRELEVANT
TO ONE OTHERHAD THEY NOT BEEN PUT TOGETHER
AS A COMPLEX WHOLE
8/8/2019 Eyeball Project
3/13
8/8/2019 Eyeball Project
4/13
The Cornea
Lights passage into the brain begins withthe cornea.The cornea isthe clear, protective film covering your pupil soyou dontaccidentally stick a pencil into youreyeball anddamageany necessary agentsthathelp you see.The cornea
also keeps in the vitreous (a kind of gel in youreyethathelpsyoureyeball retain itsshape)and slightly bendsthe lighttodirect it into your pupil.
Cornea
8/8/2019 Eyeball Project
5/13
The Iris
The iris, much liketheshutter ofa camera lens, isthe
colorful part of youreyethathelps diminishtheamount of light
that passesthrough your pupil. If you didnthavean iris, then
you would gettoo much light on a bright day and too little light
on a day you find yourselfsitting in a dungeon. And if youdidnthavean iris, everyone would look really boring and
creepy.
Iris
8/8/2019 Eyeball Project
6/13
The Pupil
The pupil isthat littlehole inside of your iris on your
eyeball.The pupil is wherethe light comes in through. If you
wereto stick your finger into youreyeto see if it was really a
hole, though, you wouldnt feel it because of your corneaand
would only succeed in hurting yourself, so take my word for it.
Pupil
8/8/2019 Eyeball Project
7/13
The Lens
The crystalline lens is, basically, a lensstuck inside of
youreyeball. It focusesthe light into your retina, just likea
contact lens or pair of glasses. If youreye wasa camera, then
your lens would bea lens. Sorry, but from now on its going
to be really complicated.
Lens
8/8/2019 Eyeball Project
8/13
TheRetina
The retina isthe film ofthe camera. Withoutthe retina,
youre justan idiot pressing a button on a plastic box.The
retinahas many layers:The pigmentepithelium (the layerthat
contains pigment used to absorb stray light rays), the
photoreceptor layer (the layerthatsignals colors), the bipolarcells (the layerthattransmitssignals from the photoreceptors
to the ganglion cells), and ganglion cells (the layerthat
transmitsthe retinal information to the midbrain).
Retina
8/8/2019 Eyeball Project
9/13
Rodsand Conesand MORE
The photoreceptor cells dont collect information on color
individually; they get information from a wide variety of
photoreceptors called rodsand cones.These rodsand
cones reactto light, orto beexact, theabsence of light.The
darker it is, the more glutamatethey release. Afterthe bipolarcellstransmitthesesignalsto the ganglion cells, they can be
interpreted asa whole, and then they arealmosttranslated
into a color. You can almostsee now.
Photoreceptors
8/8/2019 Eyeball Project
10/13
Optic Nerves
The ganglion cells now haveall the information it needs;
it just needsto getsomewhere. Almostevery sensory
instrumenthasaxons:the connections between neuronsthat
transmitelectric impulses.The ganglion cellssend impulses
throughtheiraxonstoward the optic nerves. An interestingfact isthatthe ganglion axonshaveto travel from the back of
the retina forward to reachthe optic nerves. Sincethis blocks
part ofthe retina, it createstheso-called blind spot.
Optic Nerves
8/8/2019 Eyeball Project
11/13
Lateral Geniculate Nucleus
The optic nerve passesthroughthis cerebral peduncleto be
interpreted into color, images, intensity, and brightness. Its
like going on a road trip in Spain and discovering you havea
road map, tour guide, and bottle you thinkis digestible but
youre notsure, so you stop ata gasstation and getsome
stuff in English.
http://www.pbs.org/saf/1507/teaching/teaching.htm
Lateral Geniculate
Nucleus
8/8/2019 Eyeball Project
12/13
Cortex
Everything you haveeverseen has
landed in this little gray nugget. Now you
can see.
Congratulations.http://www.pbs.org/saf/1507/teaching/teaching.htm
Primary
Visual
Cortex
8/8/2019 Eyeball Project
13/13
Sites
http://pathology.mc.duke.edu/neuropath/naw
r/sensory.html#visual
http://emeraldeye.com/eyeAnatomy.htmhttp://library.med.utah.edu/kw/hyperbrain/syl
labus/syllabus7.html
http://webvision.med.utah.edu/anatomy.html