Human Senses and Sensory Organs Vocabulary

A collection of vocabulary terms and definitions derived from a quiz on human sensory organs, covering the eye, ear, taste, smell, and general receptors.

General sense organs

Sensory units often existing as individual cells or receptor units widely distributed throughout the body.

Photoreceptors

Specialized sensory receptors that respond to light stimuli, enabling vision.

Proprioceptors

Receptors that provide information about the position of body parts or changes in muscle length or tension.

Rods and cones

Photoreceptors found in the retina that are receptors for night and day/color vision respectively.

Cornea

The transparent part of the sclera located over the iris, acting as the 'window of the eye'.

Retina

The innermost layer of the eye which contains photoreceptors known as rods and cones.

Iris

The colored part of the eye that controls the size of the pupil by contracting or dilating to regulate light entry.

Aqueous humor

The fluid found in the anterior chamber of the eye, in front of the lens.

Presbyopia

An age-related condition where the lens stiffens, causing a loss of near vision.

Middle ear

The part of the ear that houses the ossicles: malleus, incus, and stapes.

Cristae ampullaris

Sensory receptors in the semicircular canals that detect dynamic equilibrium, sensing speed and direction of head movement.

Vestibular nerve

The nerve that carries impulses from equilibrium receptors in the vestibule to form the vestibulocochlear nerve.

Cranial nerves $VII$ and $IX$

The facial and glossopharyngeal nerves that carry gustatory impulses from taste buds to the brain.

Primary taste sensations

The traditionally classified sensations of sweet, sour, bitter, and salty.

Olfactory receptors

Receptors located in the olfactory mucosa of the nasal cavity that detect odor-causing chemicals.

Pain receptors (nociceptors)

Receptors that detect injury or harmful stimuli causing pain sensations.

Tactile (Meissner) corpuscles

Corpuscles responsible for detecting fine touch and vibration sensations.

Conjunctiva

A mucous membrane that covers the front surface of the sclera and lines the eyelid, keeping the eye moist.

Lens

A transparent body behind the pupil that focuses light rays onto the retina.

Auditory (eustachian) tube

A structure that connects the middle ear to the throat to equalize pressure on both sides of the tympanic membrane.

Glaucoma

A condition caused by increased intraocular pressure that can damage the optic nerve and lead to vision loss.

Organ of Corti

Structure in the cochlea containing specialized hair cells (mechanoreceptors) that respond to sound wave-induced movement of endolymph.

Blind spot

The point where the optic nerve leaves the eye, which contains no photoreceptors.

Chemoreceptors

Receptors that respond to chemical stimuli, such as those used for taste and smell.

Mechanoreceptors

Receptors that respond to physical movement or pressure, such as those for touch and hearing.

Thermoreceptors

Sensory receptors that respond to changes in temperature.

Free nerve endings

Receptors found throughout the body that are classified as general sense receptors.

Golgi tendon receptors

General sense receptors involved in detecting muscle tension as part of proprioception.