Sense organs

Accommodation

Adjustment of the eye that allows it to focus on near or far objects by changing the shape of the lens through ciliary muscle action.

Ampulla

A widened area of each semicircular canal that contains sensory receptors for detecting rotational head movement.

Analgesia

Reduction or absence of pain perception while other sensory awareness remains intact.

Anterior chamber

The fluid-filled space between the cornea and iris that contains aqueous humor.

Aqueous humor

Clear fluid in the front of the eye that nourishes the cornea and lens while maintaining intraocular pressure.

Bulbar conjunctiva

Portion of the conjunctiva that covers the sclera of the eyeball.

Canthus

The corner of the eye where the upper and lower eyelids meet.

Choroid

The vascular middle layer of the eye that supplies nutrients to the retina.

Ciliary body

Eye structure that produces aqueous humor and contains muscles that control lens shape for focusing.

Cochlea

Spiral-shaped inner ear structure that contains sensory receptors for hearing.

Cone

Retinal photoreceptor responsible for color vision and visual detail in bright light.

Conjunctiva

Thin mucous membrane lining the eyelids and covering part of the eyeball.

Cornea

Clear, avascular outer surface of the eye responsible for most light refraction.

Endolymph

Specialized fluid within the membranous labyrinth of the inner ear.

Equilibrium

Sense of balance maintained through integration of vestibular, visual, and proprioceptive input.

Fundus

Interior back surface of the eye including the retina, choroid, and optic disc.

General sense

Sensory input distributed throughout the body, including touch, pain, temperature, and proprioception.

Proprioception

Awareness of body position and limb placement through stretch and pressure receptors.

Tapetum lucidum

Reflective layer behind the retina that enhances low-light vision.

Tympanic membrane

Thin membrane separating the external auditory canal from the middle ear that transmits sound vibrations.

Vestibule

Inner ear structure containing receptors for detecting linear motion and head position.

Vitreous humor

Clear, gel-like substance filling the back of the eye that maintains globe shape.