The Cornea
This transparent dome covers the front of the eye and helps focus light.
What is the cornea?
This fluid fills the space between the cornea and the iris.
What is aqueous humor?
This part of the eye adjusts the pupil size automatically in response to light.
What is the iris?
This part of the eye is made mostly of crystallin proteins.
What is the lens?
This muscle changes the shape of the lens to help focus.
What is the ciliary muscle?
This part of the eye contributes 60–75% of its total focusing power through refraction.
What is the cornea?
The aqueous humor is produced by this part of the eye.
What is the ciliary body?
This reflex controls how much light enters the retina.
What is the pupillary light reflex?
The lens provides about this percentage of the eye’s total focusing power.
What is 30%?
These tiny fibrous cords attach the lens to the ciliary body.
What are zonular fibers?
This layer of the eye contains 300–600 times more pain receptors than skin, making it extremely sensitive.
What is the cornea?
This is the approximate volume of aqueous humor in the anterior chamber.
What is 0.2 mL?
Eye color is determined by genetics and the concentration of this pigment.
What is melanin?
The lens continues to do this throughout your life, contributing to cataract formation.
What is grow?
The ciliary body is located between these two parts of the eye.
What are the choroid and the iris?
These are the layers of the cornea, including one recently discovered.
What are the epithelium, Bowman’s layer, stroma, and Pre-Descemet’s layer?
Aqueous humor is replaced every 1–2 hours to help maintain this pressure.
What is intraocular pressure (IOP)
Even identical twins have different patterns in this part of the eye.
What is the iris?
Older lens fibers are compressed toward the center because the lens is encapsulated and does not do this.
What is shed cells?
These structures within the ciliary body help produce aqueous humor.
What are the ciliary processes?
This process allows the cornea to bend light and focus it on the retina.
What is refraction?
Aqueous humor helps remove these from the eye: metabolic by-products, dead cells, debris, excess nutrients and proteins.
What is waste?
The iris controls the amount of light entering the eye by adjusting this structure.
What is the pupil?
Crystallin proteins in the lens are responsible for these two key optical properties.
What are transparency and refractive power?
The ciliary body includes vessels, epithelia, and this muscle that controls lens shape.
What is the ciliary muscle?