Topic 20 - Special Senses Flashcards
Eye
- how many layers?
- shape of layers?
- layers filled with what?
- 3 layers
- sphere
- filled with fluid
3 layered sphere filled with fluid
structural features of the eye
- fibrous tunic
- vascular tunic
- retina (nervous (sensory) tunic)
- Lens
- Anterior segment
- posterior segment
fibrous tunic
- list the 3 parts
- sclera (white)
- cornea (transparent)
- conjunctiva
what kind of tissue is the sclera composed of?
avascular connective tissue
what kind of tissue is the cornea composed of?
avascular connective tissue
conjunctive
- covers what?
- what does it contain?
- covers anterior sclera
- vascular mucous membrane
vascular mucous membrane
when vessels dilate = bloodshot eyes
when vessels dilate
bloodshot eyes
what parts of the fibrous tunic is composed of avascular CT?
the sclera and cornea
what part of the fibrous tunic is NOT composed of avascular CT
the conjunctiva
covers anterior sclera
conjunctiva
list the 4 parts of the vascular tunic
- choroid (posterior)
- ciliary body (anterior)
- iris
- pupil
choroid
- anterior or posterior?
- what does it contain?
- it is highly ______
- posterior
- contains melanin
- highly vascular
ciliary body
- anterior or posterior?
- ciliary ______ + ciliary ______ - focuses what?
- anterior
- ciliary muscle + ciliary processes -focus the lens
contains melanin and is highly vascular
choroid
iris
- what part of the eye?
coloured part of the eye
pupil
hole in iris
hole in iris
pupil
nervous (sensory) tunic is also called what?
retina
what are the 4 parts of the retina
- outer pigmented later
- inner neural layer
- fovea centralis
- optic disc
- outer pigmented layer
- inner neural layer
- fovea centeralis
- optic disc
part of what tunic?
nervous tunic
outer pigmented layer has:
-
inner neural layer
- how many layers of _____
- name these layers
-
3 layers of neurons
- photoreceptors
- bipolar cells
- ganglion cells
photoreceptors
- how many types?
- list the types of photoreceptors
- 2 types
- rods (black & white)
- cones (colour)
bipolar cells
x
ganglion cells
____ from ____ called ______
axons from optic nerve called cranial nerve II
cranial nerve II
axons from optic nerve
fovea centralis
- what is focused here?
- area of?
- does it contain rods? cones? both?
- where light is focused
- area of greatest visual acuity
- no rods, just cones
where light is focused
fovea centralis
no rods, just cones
fovea centralis
area of greatest visual acuity
fovea centralis
optic disc
- ____ spot where __________ and ________ exit or enter _____
- does it contain rods? cones? none? both?
- blind spot where blood vessels + optic nerve EXIT eye
- no rods OR cones
blind spot where blood vessels + optic nerve exit eye
optic disc
has no rods or cones
a) outerpigmented layer
b) inner neural layer
c) fovea centralis
d) optic disc
OPTIC DISC
lens
- vascular or avascular?
- transparent or not transparent?
- what = clouding of lens
avacular, transparent
cataracts
cataracts
clouding of lens
anterior segment
- anterior or posterior to lens?
- what does it contain?
- _____ similar to what?
- anterior to lens
- contains aqueous humor
- fluid similar to plasma
fluid similar to plasma
aqueous humor
anterior to lens
anteior segment
posterior segment
- anterior or posterior to lens?
- contains what?
- posterior to lens
- contains vitreous humor