Human Vision Flashcards

Flashcards based on lecture notes about Human Vision

Pupil

An opening through which light enters the eye.

Iris

The colored circle that surrounds the pupil and controls the amount of light that enters the eye. It contracts for more light and relaxes when there is less light.

Cornea

Transparent tissue covering the iris and pupil.

Lens

Convex structure behind the pupil that can change shape using ciliary muscles to bend light and form an image on the retina.

Aqueous Humor

A watery fluid located in the space between the cornea and the lens.

Sclera

The main structural component of the eye, also known as the white of the eye.

Retina

Contains sensory cells that produce an image with the brain; found on the back wall inside the eye.

Refraction

The bending of light as it passes through a lens or other transparent object.

Converging Lens

A lens that has at least one convex surface and brings parallel light rays towards a common point (focal point).

Diverging Lens

A lens that has concave surfaces and causes parallel rays to spread apart.

Myopia

Nearsightedness; the inability to focus on distant objects. Corrected with diverging (concave) lenses.

Hyperopia

Farsightedness; the inability to focus on close objects. Corrected with converging (convex) lenses.

Optic Nerve

The nerve that carries information from the sensory receptors in the eye to the brain.

Blind Spot

The area on the retina where the optic nerve exits the eye, which has no sensory receptors.

Rods

Sensory cells in the retina that are sensitive to low light, providing black and white vision.

Cones

Sensory cells in the retina that are used to detect color, especially red, green, and blue.

Vitreous Humor

The jelly-like substance in the main body of the eye.

Choroid

The layer that provides blood and nutrients to the retina.