Nervous System Exam 4 Study Guide Flashcards

A comprehensive set of vocabulary flashcards covering the anatomy, cell types, divisions, and functions of the nervous system based on the Exam 4 Study Guide.

Neuron Parts

The basic components of a neuron consisting of the dendrite, axon, and cell body.

Dendrite

A neuronal process that conducts nerve impulses toward the cell body.

Circumvallate papillae

A type of lingual papillae that forms a "V" pattern at the back of the tongue.

Neuroglial cells

Supporting cells in the nervous system that provide nutrition and structural support for neurons.

Interneuron

A type of neuron, primarily found in the CNS, that typically has short dendrites and either a long or short axon.

Schwann cells

Neuroglial cells in the peripheral nervous system (PNS) that produce layers of membrane containing myelin.

Nodes of Ranvier

The gaps found between segments of the myelin sheath along an axon.

Multiple sclerosis

A disease of the myelin sheath that prevents neurons from effectively transmitting action potentials.

Multipolar neurons

The structural classification for all motor neurons.

Action Potential Propagation

The process of a nerve impulse traveling down an axon, which occurs fastest in thick, myelinated axons.

Synaptic cleft

The gap between the plasma membranes of a neuron conducting a signal and the cell receiving that signal.

Mechanoreceptor

A type of sensory receptor that detects touch, stretch, and pressure.

Dura mater

The tough, superficial meningeal layer that adheres to the underside of the cranial cavity.

Hindbrain

The developmental region of the brain composed of the metencephalon and the myelencephalon.

Longitudinal fissure

The deep groove that separates the two cerebral hemispheres.

Cones

The specific type of tightly packed photoreceptors found within the fovea of the eye.

Pituitary Gland

A small part of the brain responsible for producing and releasing hormones.

Effector

A structure, cell, or organ that responds to impulses from peripheral neurons that synapse upon it.

Gyri and Sulci

The elevated ridges of tissue on the cerebral surface ($Gyri$) and the shallow grooves ($Sulci$) that separate them.

Broca’s area

The specific part of the brain that coordinates the ability to vocalize words.

Brain Stem

The part of the brain that houses the midbrain, pons, and medulla oblongata.

Afferent nerves

Nerves that carry sensory information toward the central nervous system; also known as sensory nerves.

Efferent nerves

Nerves that carry motor impulses away from the central nervous system; also known as motor nerves.

Reticular activating system (RAS)

The area of the brain stem involved in consciousness and the awake/sleep cycle.

Hypothalamus

The brain region that controls temperature, endocrine activity, metabolism, thirst, food intake, and water balance.

Medulla oblongata

The portion of the brain stem containing vital centers for controlling heart rate, breathing, blood pressure, swallowing, and vomiting.

Cerebellum

The part of the brain responsible for loss of muscle coordination if damaged; it provides precise timing for skeletal muscle contraction.

Sympathetic nervous system

The division of the autonomic nervous system responsible for the "fight-or-flight" response during threatening situations.

Parasympathetic nervous system

The division of the autonomic nervous system that promotes digestion, retards heartbeat, and causes pupil contraction.

Vascular tunic

The middle layer of the eye composed of the iris, ciliary body, and choroid.

Reflex arc pathway

The sequence of a reflex: receptor $\rightarrow$ afferent neuron $\rightarrow$ interneuron $\rightarrow$ efferent neuron $\rightarrow$ effector.

Corpora quadrigemina

The midbrain structure involved in visual reflexes (eye tracking) and auditory reflexes ("startle reflex").

Anterior root

The portion of a spinal nerve that contains only motor neurons.

Posterior root

The portion of a spinal nerve that contains only sensory neurons.

Static Equilibrium Receptors

Receptors housed within the utricle and saccule of the inner ear.

Vagus nerve

The longest cranial nerve, which sends branches to the viscera throughout the ventral body cavities.

Cerebral nuclei

Structures that control large subconscious movements, such as swinging the arms while walking.

Tentorium cerebelli

The meningeal structure located within the transverse fissure.

Falx cerebri

The meningeal structure located within the longitudinal fissure.

Cranial Nerve Count

Humans possess $12$ pairs of these nerves.

Spinal Nerve Count

Humans possess $31$ pairs of these nerves.

Oligodendrocytes

The glial cells that myelinate and insulate axons within the central nervous system (CNS).

Astrocytes

Glial cells that help form the blood-brain barrier and provide structural support.

Ependymal cells

Glial cells that line the brain ventricles and central canal to help form cerebrospinal fluid (CSF).

Microglial cells

Glial cells that defend the central nervous system against pathogens via phagocytosis.

Nerve

A cable-like bundle of parallel axons found in the peripheral nervous system.

Tract

A bundle of parallel axons located within the central nervous system.

Epineurium

The fibrous outer layer that covers a nerve.

Infundibulum

The structure that connects the pituitary gland to the hypothalamus.

Spinal Cord Extent

The anatomical structure extending from the foramen magnum to $L1$ – $L2$.