This clear, curved structure is the first major part of the eye that bends incoming light.
What is the cornea?
The main thing entering your eye that makes vision possible.
What is light?
The clear tissue at the front of the eye has several layers and is known as this.
What is the cornea?
The long, narrow photoreceptor is this type of cell.
What is a rod?
This is the light-sensitive pigment found in rod cells.
What is rhodopsin?

This opening allows light to enter the eye.
What is the pupil?
The curved shape of the cornea causes incoming light to do this.
What is bend/refract?
The outermost layer of the cornea.
What is the epithelium?
This cell is associated with color vision.
What is a cone?
Rhodopsin contains a protein known as this.
What is opsin?
This structure controls how large or small the pupil becomes.
What is an iris?
The iris changes the pupil's size primarily to control this.
What is the amount of light entering the eye?
The middle corneal layer contains regularly arranged collagen fibers.
What is the stroma?
These photoreceptors are especially useful in poorly lit conditions.
What is a rod?
Light causes this molecule inside rhodopsin to change shape.
What is retinal?
Located behind the pupil, this structure helps focus incoming light onto the retina.
What is the lens?
The cornea and lens work together so light reaches this structure at the back of the eye.
What is the retina?
The regular arrangement of collagen helps the cornea maintain this important optical property.
What is transparency/clarity?
Rods and cones contain many stacked membranes because the stacks provide more of this for light-sensitive pigments.
What is surface area?
Retinal is derived from this vitamin.
What is vitamin A?
This tissue contains the cells that detect light.
What is the retina?
The rounded shape of the eye helps position the retina behind these two curved structures, allowing incoming light to be focused.
What are the cornea and lens?
This inner corneal layer regulates water in the stroma, preventing swelling and cloudiness.
What is the endothelium?
This portion communicates information to other retinal neurons.
What is the synaptic terminal?
When retinal changes from bent to straight, it changes opsin's shape and begins this biological process.
What is a signaling pathway?