Somatic and Special Senses Practice Flashcards

Flashcards covering somatic sensory receptors, classification of senses, and the special senses of smell, taste, hearing, equilibrium, and vision.

Receptor

Any specialized structure used to detect a stimulus, which is anything that causes a response.

Chemoreceptors

Receptors that respond to chemicals, specifically for smell and taste.

Thermoreceptors

Receptors located in the skin that respond to temperature changes.

Nociceptors

Receptors that respond to painful stimuli or irritating touch/temperature stimulus like an itch.

Mechanoreceptors

Receptors that respond to physical change.

Photoreceptors

Receptors that respond to light.

Osmoreceptors

Receptors that respond to the osmotic pressure of body fluids.

Visceroceptors

Internal receptors that pick up changes in internal organs.

Externoceptors

Sensory receptors located in external areas.

Proprioceptors

Receptors that monitor position changes in skeletal muscle, joints, and tendons.

Merkle cells/discs

Unencapsulated tactile receptors responsible for light pressure.

Root hair plexus

Receptors found around the hair bulb (hair follicle receptors) used to detect hair movement.

Meissner’s corpuscle

Encapsulated receptors located in the papillary layer of the dermis responsible for light touch.

Pacinian corpuscle

Encapsulated receptors located in the reticular layer of the dermis responsible for deep pressure and vibrations.

Krause’s end bulb

Encapsulated receptors for light touch and temperature that may be responsible for cold mechanoreception.

Ruffini corpuscle

Encapsulated receptors for touch and temperature that may be responsible for hot temperature.

Muscle spindles

Mechanoreceptors in skeletal muscles that monitor the length of muscle fiber stretch.

Golgi tendon receptors

Receptors in tendons that deal with muscle tension and the contraction of tendons and skeletal muscle.

Joint kinesthetic receptors

Proprioceptors that monitor stretch in articular capsules.

Olfactory cells

Chemoreceptors in the nose responsible for the sense of smell.

Gustatory cells

Chemoreceptors in taste buds responsible for the sense of taste.

Umami

One of the five basic taste sensations, elicited by the amino acid glutamate.

Organ of Corti

The receptor structure in the ear containing hair cells that are deflected to create an action potential for hearing.

Cristae ampullaris

Mechanoreceptors in the ear used for equilibrium.

Auricle (pinna)

The external part of the ear that helps direct sound waves into the external auditory meatus.

Tympanic membrane

Also known as the eardrum, it moves sound waves to the auditory ossicles.

Auditory ossicles

The three small bones of the middle ear: the malleus (hammer), incus (anvil), and stapes (stirrup).

Perilymph

A fluid similar to CSF that ripples to move the vestibular membrane and transmit sound waves.

Endolymph

The fluid found inside the cochlear duct.

Vestibular apparatus

The combination of the vestibule and semicircular canals which contain sense organs for balance.

Rods

Photoreceptors in the retina responsible for monochrome (black and white) vision.

Cones

Photoreceptors in the retina responsible for color vision.

Iris

The pigmented part of the eye that regulates the size of the pupil.

Lens

A structure in the eye that changes shape to focus light on the retina.

Ciliary muscle

The muscle responsible for changing the lens shape during accommodation.

Retina

The inner layer of the eye where images are formed and photoreceptors (rods and cones) are located.

Optic disc

The area of the retina known as the blind spot.

Rhodopsin

The chemical in photoreceptors that breaks down when reached by light, causing a membrane potential.

Near point

The closest point of clear focus, which changes as a person reaches approximately $50$ years of age.

Far point of vision

The distance beyond which the lens does not need to change shape to focus, typically $20\,\text{ft}$.

Accommodation

The process of changing the lens shape using ciliary muscles to increase refractory power for close vision.

Convergence

The medial rotation of the eyeballs toward the object being viewed.

Myopia

A vision disorder known as 'near sightedness' where distant objects are focused in front of the retina.

Hyperopia

A vision disorder known as 'far sightedness' where distant objects are focused behind the retina.

Presbyopia

The age-related change in the eye's ability to focus on close objects.