Sensory Receptors & Special Senses Vocabulary

A set of 37 vocabulary flashcards covering sensory receptors, taste, smell, vision, hearing, and balance.

Cutaneous sensory receptors

Skin receptors that detect touch, pressure, pain, and temperature.

Visceral sensory receptors

Receptors in internal organs that sense stretch, chemical changes, and irritation.

Papillae (tongue)

Small bumps on the tongue that house taste buds.

Taste buds

Clusters of gustatory receptor cells that respond to chemicals dissolved in saliva.

Cranial nerves for taste

Facial nerve (VII) and Glossopharyngeal nerve (IX) that carry gustatory signals.

Olfactory system (origin)

Begins in the peripheral structures of the nasal cavity.

Olfactory receptor neurons

Sensory neurons located in the olfactory epithelium that detect odorants.

Olfactory bulb

Brain structure where olfactory receptor neurons synapse with secondary neurons.

Accessory structures of the eye

Eyebrows, palpebrae, conjunctiva, lacrimal apparatus, and extrinsic eye muscles.

Orbit

Bony socket and surrounding soft tissues that house the eye.

Layers of the eye wall

Fibrous tunic, vascular tunic, and neural (sensory) tunic.

Retina

Neural tunic containing photoreceptors that convert light into nerve signals.

Aqueous humor

Clear fluid filling the anterior segment of the eye.

Vitreous humor

Gel-like substance filling the posterior segment of the eye.

Pathway of light through the eye

Cornea → aqueous humor → pupil → lens → vitreous humor → retina.

Phototransduction site

Retina, where light energy is converted into action potentials.

Bipolar cells (retina)

Neurons that receive signals from photoreceptors and pass them to ganglion cells.

Retinal image projection

Visual field is projected onto the retina as an inverted, reversed image.

Optic nerve vs. optic tract

Same axons; name changes from peripheral (nerve) to central (tract) at the chiasm.

Rods

Photoreceptors activated by dim light, enabling night vision.

Cones

Photoreceptors activated by bright light, responsible for color and day vision.

Rod distribution

Located predominantly in the peripheral retina.

Cone distribution

Concentrated in the fovea centralis.

Rhodopsin

Light-sensitive pigment in rods that requires vitamin A.

Parts of the ear

Outer ear, middle ear, and inner ear.

Outer ear components

Auricle, auditory canal, and tympanic membrane.

Middle ear components

Auditory ossicles and Eustachian (pharyngotympanic) tube.

Inner ear components

Cochlea and vestibule (including semicircular canals).

Stapes

Ossicle that fits into the oval window to transmit vibrations.

Cochlear pressure waves

Created by stapes vibration at the oval window, causing fluid motion in the cochlea.

Organ of Corti

Structure within the cochlea containing hair cells for hearing.

Cochlear nerve

Branch of cranial nerve VIII that carries auditory signals to the brain.

Temporal lobe (auditory cortex)

Brain region that processes sound information.

Vestibule function

Detects static equilibrium and linear acceleration.

Vestibule structures

Saccule and utricle within the inner ear.

Semicircular canals

Three fluid-filled loops that detect dynamic equilibrium (rotational movement).

Cupula mechanism

Fluid movement bends the cupula and stereocilia of hair cells in semicircular canals to sense head rotation.