The Human Eye: Anatomy, Photoreceptors, and Vision Disorders

Vocabulary practice flashcards covering eye anatomy, ocular layers, photoreceptors, visual pathways, and common vision disorders.

Sclera

The outer white layer of the eye that transitions into the clear cornea, functioning to protect and support the eye.

Choroid

The middle layer of the eye containing blood vessels that provide nourishment.

Retina

The inner layer of the eye that houses photoreceptors responsible for capturing light signals.

Cornea

A clear structure that protects the eye and refracts light towards the pupil.

Iris

An opaque disk of tissue determining eye colour that regulates the amount of light entering the eye.

Pupil

The opening or gap enclosed by the iris through which light enters the interior of the eye.

Lens

The structure controlled by ciliary muscles that focuses images directly onto the retina.

Ciliary muscles

Muscles that control the curvature and shape of the lens to focus images onto the retina.

Optic disc

The blind spot of the eye where the optic nerve attaches to the retina.

Optic nerve

The nerve that carries visual messages from the retina to the occipital lobe of the brain.

Rods

Photoreceptor cells in the retina responsible for vision at low light levels.

Cones

Photoreceptor cells in the retina responsible for colour vision and vision at higher light levels.

Fovea centralis

The region at the center of the retina containing closely packed cones that produces sharp vision.

Myopia

Nearsightedness; a refractive disorder where images focus in front of the retina, causing distant objects to appear blurry.

Hyperopia

Farsightedness; a refractive disorder where images focus behind the retina, causing close objects to appear blurry.

Astigmatism

A vision disorder caused by an imperfect curvature in the eye, resulting in blurriness across all images.

Cataract

A visual disorder characterized by the clouding of the eye's lens.

Optic chiasma

The X-shaped anatomical structure in the visual pathway where crossing over of optic nerve fibers takes place.

Optic tract

The continuation of visual nerve pathways leading from the optic chiasm towards the visual area of the thalamus and the visual cortex.

Occipital lobe

The region of the cerebral cortex that receives visual input from the optic nerve and contains the visual cortex.

Aqueous humour

The fluid filling the anterior segment of the eyeball between the cornea and the lens.

Vitreous humour

The gel-like fluid filling the posterior cavity of the eyeball behind the lens.