Sensory Receptors and Their Functions

These flashcards cover key vocabulary related to sensory receptors, their functions, and associated systems based on the lecture notes provided.

Sensory Receptors

Transducers that convert stimulus energy into electrical energy.

Receptive Field

The distribution area of the endings of a sensory neuron, smaller fields allow more precise stimulus localization.

Sensation

A stimulus that we are consciously aware of.

Modality

The type of stimulus based on a 'labeled line' that identifies stimulus types in the brain.

Receptor Adaptation

Decreased sensitivity to continuous stimulus.

Tonic Receptors

Show limited adaptation and respond continuously to stimuli.

Phasic Receptors

Adapt rapidly and respond only to new stimuli.

Exteroceptors

Detect stimuli from the external environment.

Interoceptors

Detect stimuli from internal organs.

Proprioceptors

Detect body and limb movements.

Chemoreceptors

Detect chemicals dissolved in fluid.

Thermoreceptors

Detect changes in temperature.

Photoreceptors

Detect changes in light intensity, color, and movement.

Mechanoreceptors

Detect distortion of cell membrane, involved in touch, pressure, vibration, and stretch.

Nociceptors

Detect painful stimuli.

General Sense Receptors

Simple structures distributed throughout the body.

Special Sense Receptors

Specialized receptors in complex sense organs of the head.

Taste Buds

Onion-shaped organs housing gustatory receptors.

Olfaction

The sense of smell, detection of odorants dissolved in the air.

Gustation

The sense of taste, detecting tastants using taste buds.

Cochlea

A spiral organ in the inner ear involved in hearing.

Hair Cells

Receptors in the cochlea that release neurotransmitters to sensory neurons.

Ampulla

Enlarged region of semicircular canals containing sensory receptors.

Crista Ampullaris

Structure within the ampulla that contains hair cells and supports cells.

Macula

Receptor for static equilibrium and linear acceleration.

Stereocilia

Tiny hair-like projections on hair cells that detect mechanical changes.

Kinocilium

Long cilium on hair cells involved in balance and equilibrium.

Endolymph

Fluid within the membranous labyrinth, rich in K+.

Transduction

The process by which sensory stimuli are converted into nerve impulses.

Basilar Membrane

Membrane within the cochlea that vibrates in response to sound waves.

Vestibulocochlear Nerve (CN VIII)

The cranial nerve responsible for transmitting sound and equilibrium information.

Olfactory Epithelium

The sensory receptor organ for smell located in the nasal cavity.

Gustatory Microvillus

Taste hair that forms the dendritic ending of gustatory cells.

Optic Nerve

The nerve that carries visual information from the retina to the brain.

Phototransduction

Converting light into electrical signals in photoreceptors.

Rhodopsin

Photopigment found in rods that detects light.

Fovea Centralis

The area of the retina with the highest concentration of cones; responsible for sharp vision.

Blind Spot

Region of the retina where the optic nerve exits, lacking photoreceptors.

Lens

Structure that changes shape to focus light on the retina.

Vitreous Humor

Transparent jelly-like substance in the posterior cavity of the eye.

Aqueous Humor

Fluid in the anterior cavity of the eye that nourishes structures.

Tympanic Membrane

The eardrum, which vibrates in response to sound waves.

Auditory Ossicles

The three tiny bones in the middle ear that transmit sound.

Cochlear Duct

The membranous labyrinth in the cochlea.

Otoliths

Calcium carbonate crystals that help detect head position.

Tectorial Membrane

Governs the movement of hair cells during sound wave stimulation.

Round Window

Membrane-covered opening that equalizes pressure in the inner ear.

External Acoustic Meatus

The ear canal that leads to the tympanic membrane.

Semicircular Ducts

Structures in the inner ear that detect rotational head movements.