Parts of the eye Flashcards
Forms a white capsule around the eye. What is its function?
sclera: tough, fibrous sclera serves as the insertion point for external muscles that move the eyeballs within their sockets (maintains shape of the eye)
sclera turns into this at its anterior surface where it is specialized into the clear what? What does it do?
cornea, and it protects the lens
vascular layer - choroid is a part of this, and it becomes what at the front, and what does this do? What does the vascular layer help with?
Iris - choroid layer is specialized in the front to become the iris (structure that gives your eye their color). Helps to adjust pupil size to adjust the amount of light that is let into the eye.
Tiny fibers that are attached to ________ muscle? What do these fibers do? As we age what happens?
Zonules. These fibers hold the lens in place, and help adjust the shape of the lens. Zonules weaken with age.
Changing the shape of the lens does what?
Changes the focus
Forms the inner, posterior surface of the eye, containing numerous types of neurons including the sensory cells of the eyes (photoreceptors) - aka rods and cones
retina
a central, shallow pit within the macula containing a high density of cones, but relatively few light-obstructing retinal neurons – this region is specialized to deliver what?
fovea - or fovea centralis. Specialized to deliver the highest visual acuity (sharpest vision). This is where I want my images to land.
What does the lens do?
bends light to focus it on the retina
a distinct, circular region toward the nasal side of the retina where neurons carrying information from the photoreceptors exit the eye as the _______.
optic disc, optic nerve
_______ also travel through the optic disc: these enter the eye at the optic disc and branch extensively over the inner surface of the retina
blood vessels
