A&P Final!!

Sense

The ability of the body to detect a stimulus (change in the environment).

General Sense

A sense in which the receptor is distributed throughout the body (e.g., touch, pressure, temperature, pain, proprioception).

Special Sense

A sense in which the receptor is located with a specialized organ (e.g., vision, hearing, equilibrium, taste, and smell).

Sensation

The activation of sensory receptors by a stimulus, leading to a neural signal sent to the central nervous system.

Perception

The conscious awareness of sensory information processed in the brain.

Receptive Field

The region within which a particular sensory neuron can be activated by a given stimulus.

Peripheral Adaptation

A process by which sensory receptors reduce their response to a constant stimulus over time.

Central Adaptation

A process by which the central nervous system decreases its perception of a constant stimulus over time.

Olfactory System

The sensory system responsible for the sense of smell; odorants detected by olfactory receptor cells in the nasal cavity.

Gustatory System

The sensory system responsible for the sense of taste; chemical stimuli detected by gustatory receptor cells within taste buds of the tongue.

Visual System

The sensory system responsible for vision; light detected by photoreceptors in the retina of the eyes.

Auditory System

The sensory system responsible for hearing; sound waves detected by hair cells within the cochlea of the inner ear.

Vestibular System

The sensory system responsible for recognizing linear and rotational body movement; movement detected by hair cells in the inner ear.

Odorant

An air-borne chemical that is capable of activating olfactory receptors to produce a perception of smell.

Olfactory Bulb

The bulbous structure located on the underside of the frontal lobe of the brain where olfactory receptor cells (olfactory nerve, CN I) synapse with secondary neurons.

Olfactory Tract

One of two bundles of axons extending from the olfactory bulb to brain regions involved in odor perception and response.

Basal (Stem) Cells

The stem cells found in the olfactory epithelium or gustatory taste buds that regenerate olfactory and gustatory receptor cells.

Olfactory Nerve (CN I)

The cranial nerve formed by olfactory receptor cells that transmits sensory information related to smell from the nasal cavity to the olfactory bulb.

Tongue

A muscular organ in the mouth involved in taste, speech, and food manipulation.

Lingual Papillae

Projections of the epithelial surface of the tongue that contain taste buds.

Taste Bud

A cluster of gustatory receptor cells and supporting cells responsible for detecting taste stimuli.

Gustatory Receptor

A sensory receptor located within a taste bud that is activated by taste stimuli (dissolved chemicals).

Gustatory Receptor Cell

A specialized cell within the taste bud that binds dissolved tastants and transmits signals to afferent sensory neurons.

Tastant

A chemical capable of activating a gustatory receptor to produce a perception of taste.

Umami

One of the five basic taste modalities, associated with the savory flavor of amino acids like glutamate; 'delicious' or 'tasty' (Japanese).

Iris

The pigmented muscular structure in the eye that controls the diameter of the pupil.

Pupil

The opening in the center of the iris that allows light to enter the eye and reach the retina.

Sclera

The white, fibrous outer layer of the eyeball that provides protection and shape.

Anterior Cavity

The smaller, fluid-filled space in the eye located between the cornea and the lens, containing aqueous humor.

Posterior Cavity

The larger space in the eye located behind the lens, filled with vitreous humor.

Focal Point

The point at which light rays converge after passing through the lens, ideally focused on the retina for clear vision.

Accommodation

The process by which the lens changes shape in order to position the focal point on the retina, thereby focusing on near or distant objects.

Myopia

The condition of nearsightedness, where distant objects appear blurry due to the focal point being anterior to the retina.

Hyperopia

The condition of farsightedness, where close objects appear blurry due to the focal point being posterior to the retina.

Rod Photoreceptor

A type of photoreceptor cell in the retina that is activated by light intensity, useful in low light and responsible for night vision.

Cone Photoreceptor

A type of photoreceptor cell in the retina that is activated by light wavelength (i.e., color), useful in bright light.

Optic Disc

The region at the back of the eye where the optic nerve (CN II) exits; known as the 'blind spot' due to lack of photoreceptors.

Macula

The central region of the retina, lateral to the optic disc, which contains a high density of photoreceptors and is responsible for sharp central vision.

Fovea Centralis

The central region of the macula which contains densely packed cone photoreceptors only.

Depth Perception

The ability to judge the distance and three-dimensional relationship of objects based on overlaid visual input from both eyes.

External Ear

The outer part of the ear including the auricle and external acoustic meatus.

Middle Ear

The air-filled chamber between the tympanic membrane and cochlea which contains the auditory ossicles and transfers auditory signals from the external to inner ear.

Inner Ear

The fluid-filled structure within the temporal bone that contains the cochlea for hearing and vestibular system for balance.

Auricle

The external, visible part of the ear that collects and directs sound waves into the auditory canal; pinna (zoology).

External Acoustic (Auditory) Meatus

The canal leading from the external ear to the tympanic membrane; ear canal.

Ceruminous Gland

A gland located in the external auditory canal that secretes earwax (cerumen) to protect the ear.

Tympanic Membrane

A thin membrane that separates the external ear from the middle ear and vibrates in response to incoming sound waves; eardrum.

Auditory Ossicles

Three small bones in the middle ear (malleus, incus, stapes) that transmit sound vibrations to the inner ear.

Malleus

The first of the auditory ossicles, attached to the tympanic membrane; 'hammer.'

Incus

The middle auditory ossicle, connecting the malleus to the stapes; 'anvil.'

Stapes

The third auditory ossicle that transmits vibrations to the oval window of the cochlea; 'stirrup.'

Auditory Tube

A canal that connects the middle ear to the nasopharynx, helping to equalize pressure; eustachian tube, pharyngotympanic tube.

Oval Window

An oval-shaped, membrane-covered opening in the cochlea where the stapes transmits sound vibrations into the inner ear.

Cochlea

A spiral-shaped structure in the inner ear that contains the sensory receptors for hearing.

Semicircular Canals

Three loop-shaped structures in the inner ear involved in sensing rotational movements of the head.

Vestibule

The central part of the inner ear between the cochlea and semicircular canals involved in detecting linear movement and head position.

Hair Cell

A specialized mechanoreceptor in the inner ear that responds to movement of fluid or membrane deflection.

Stereocilia

The small, hair-like projections on the surface of hair cells that detect mechanical movement.

Kinocilium

A single, larger cilium found on hair cells that helps determine the direction of movement.

Semicircular Ducts

Fluid-filled ducts within the semicircular canals.

Ampulla

The expanded region at the base of each semicircular duct containing hair cells that respond to fluid movement during head rotation.

Utricle

An otolith organ in the vestibule that detects horizontal linear movement and head position.

Saccule

An otolith organ in the vestibule that detects vertical linear movement and head position.

Cerebrum

The most superior and largest part of the human brain containing gyri (folds) and sulci/fissures (grooves), responsible for higher cognitive functions, sensory perception, voluntary motor control, and complex thought processes.

Cerebellum

A part of the brain inferior to the cerebrum and posterior to the brainstem, responsible for movement coordination.

Diencephalon

A part of the brain located between the cerebrum and the brainstem, containing structures such as the thalamus, hypothalamus, and epithalamus, which regulate sensory processing and autonomic functions.

Brainstem

The part of the brain that connects to the spinal cord, responsible for basic life-sustaining functions (i.e., heart rate, breathing, and reflexes).

Lateral Ventricles

A pair of C-shaped cavities within each cerebral hemisphere that produces cerebrospinal fluid.

Third Ventricle

A narrow, midline cavity in the diencephalon that connects the lateral ventricles to the fourth ventricle and produces cerebrospinal fluid.

Fourth Ventricle

A cavity located between the brainstem and cerebellum, serving to produce and pass cerebrospinal fluid from the ventricles to the subarachnoid space or central canal of the spinal cord.

Interventricular Foramen

A small passageway that connects each lateral ventricle to the third ventricle.

Cerebral Aqueduct

A small passageway through the midbrain that connects the third and fourth ventricles.

Pia Mater

The delicate, innermost layer of the meninges that directly covers the brain and spinal cord, providing protection and support.

Arachnoid Mater

The middle layer of the meninges, featuring a web-like structure that helps cushion the brain and spinal cord.

Dura Mater

The tough, outermost layer of the meninges that provides structural support and protection for the brain and spinal cord.

Arachnoid Membrane

The thin arachnoid mater that separates the subarachnoid space from the dura mater.

Arachnoid Trabeculae

Web-like strands of connective tissue that extend through the subarachnoid space, connecting the arachnoid membrane to the pia mater.

Subarachnoid Space

The space between the arachnoid mater and pia mater, filled with cerebrospinal fluid that cushions and protects the brain and spinal cord.

Periosteal Layer (of the Dura Mater)

The outer layer of the dura mater that is attached to the inner surface of the skull.

Meningeal Layer (of the Dura Mater)

The inner layer of the dura mater that helps form dural folds.

Dural Space

The space between the periosteal and meningeal layer of the dura mater, where cerebrospinal fluid is reabsorbed into the blood.

Cerebrospinal Fluid

A clear, watery fluid that is produced in the ventricles and circulates through the ventricles and subarachnoid space, providing cushioning, nutrient delivery, and waste removal for the brain and spinal cord.

Arachnoid Granulations

Small protrusions of the arachnoid mater through the meningeal layer of the dura mater and into the dural space that allows for the passage of cerebrospinal fluid to be reabsorbed into the bloodstream.

Medulla Oblongata

The most inferior part of the brainstem that is directly connected to the spinal cord, responsible for autonomic functions such as heart rate, breathing, and blood pressure regulation.

Pons

The middle part of the brainstem that acts as a bridge or connection between different parts of the brain, involved in motor control, sensory processing, and communication between the cerebrum and cerebellum.

Ascending Tracts

A neural pathway in the spinal cord and brainstem that transmits sensory information from the body to the brain.

Descending Tracts

A neural pathway in the spinal cord and brainstem that transmits motor commands from the brain to the muscles.

Midbrain

The most superior part of the brainstem, involved in visual and auditory processing, motor control, and the regulation of consciousness.

Superior Colliculus

A pair of nuclei in the midbrain that processes visual information and helps coordinate responsive eye and head movements.

Inferior Colliculus

A pair of nuclei in the midbrain that processes auditory information and helps coordinate responsive eye and head movements to aid in sound localization.

Right Hemisphere (of the cerebellum)

The right half of the cerebellum, separated by the vermis.

Left Hemisphere (of the cerebellum)

The left half of the cerebellum, separated by the vermis.

Arbor Vitae

The white matter of the cerebellum which is in the shape of a branching tree (arbor, tree; vitae, life).

Epithalamus

The superior part of the diencephalon that includes the choroid plexus of the 3rd ventricle and the pineal gland that regulates sleep-wake cycles.

Thalamus

A major relay center in the diencephalon that processes and transmits sensory information from the body to the cerebral cortex.

Hypothalamus

The anteroinferior part of the diencephalon with dual roles in the nervous and endocrine systems; regulates homeostasis, including hunger, thirst, body temperature, and the autonomic nervous system.

Pineal Gland

A small endocrine gland in the epithalamus that produces melatonin, which regulates sleep-wake cycles.

Basal Nuclei

Groups of neuronal cell bodies within the cerebrum that play a role in voluntary motor control and movement regulation.

Gyrus

A raised ridge (fold) on the surface of the brain (plural, gyri).

Sulcus

A shallow groove between gyri on the brain (plural, sulci).