Which structures are part of the structure of the eye?

Which structures are part of the structure of the eye?

• A. Cornea, pupil, iris
• B. The ear bones and eardrum
• C. Cornea, pupil, iris, lens, retina
• D. The optic nerve and brain

Answer: (C)

The structures that make up the eye include the cornea, pupil, iris, lens, and retina. The cornea is the clear front surface that begins bending incoming light; the pupil is the opening whose size the iris adjusts to regulate how much light enters; the iris is the colored part that controls that aperture. Behind the pupil sits the lens, which fine-tunes focus so images form sharply on the retina, the light-sensitive layer at the back of the eye. The retina contains cells that convert light into neural signals sent to the brain. The ear bones and eardrum belong to the hearing system, not the eye. The optic nerve and brain are part of vision but lie outside the eye itself—the optic nerve carries signals from the retina to the brain, where they’re processed. Thus, the full set of eye structures listed is cornea, pupil, iris, lens, and retina.

The structures that make up the eye include the cornea, pupil, iris, lens, and retina. The cornea is the clear front surface that begins bending incoming light; the pupil is the opening whose size the iris adjusts to regulate how much light enters; the iris is the colored part that controls that aperture. Behind the pupil sits the lens, which fine-tunes focus so images form sharply on the retina, the light-sensitive layer at the back of the eye. The retina contains cells that convert light into neural signals sent to the brain. The ear bones and eardrum belong to the hearing system, not the eye. The optic nerve and brain are part of vision but lie outside the eye itself—the optic nerve carries signals from the retina to the brain, where they’re processed. Thus, the full set of eye structures listed is cornea, pupil, iris, lens, and retina.