| Term 
 | Definition 
 
        | fast-acting control system that employs nerve impulses to trigger muscle contraction or gland secretion |  | 
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        | Term 
 
        | central nervous system (CNS) |  | Definition 
 
        | the brain and the spinal cord |  | 
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        | peripheral nervous system (PNS) |  | Definition 
 
        | a system of nerves that connects the outlying parts of the body with the central nervous system |  | 
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 | Definition 
 
        | carrying to or toward a center |  | 
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        | nerve cells that carry impulses toward the central nervous system |  | 
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 | Definition 
 
        | carrying away or away from |  | 
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 | Definition 
 
        | neurons that conduct impulses away from the central nervous system |  | 
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        | a division of the peripheral nervous system; also called the voluntary nervous system |  | 
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        | self-directed; self-regulating; independent |  | 
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        | the division of the nervous system that functions involuntarily; innervates cardiac muscle, smooth muscle, and glands |  | 
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        | the nonneuronal tissue of the central nervous system that performs supportive and other functions; also called glia |  | 
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 | Definition 
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 | Definition 
 
        | cells of the nervous system specialized to transmit messages throughout the body |  | 
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 | Definition 
 
        | the branching extensions of neurons that carry electrical signals to the cell body; the receptive portion of a nerve cell |  | 
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 | Definition 
 
        | neuron process that carries impulses away from the nerve cell body; efferent process; the conducting portion of a nerve cell |  | 
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 | Definition 
 
        | chemical released by neurons that may, upon binding to receptors of neurons or effector cells, stimulate or inhibit them |  | 
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 | Definition 
 
        | the region of communication between neurons |  | 
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 | Definition 
 
        | the fluid-filled space at a synapse between neurons |  | 
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 | Definition 
 
        | a white, fatty lipid substance |  | 
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 | Definition 
 
        | a dense central body in most cells containing the genetic material of the cell |  | 
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 | Definition 
 
        | a group of nerve cell bodies located in the peripheral nervous system |  | 
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 | Definition 
 
        | a collection of nerve fibers in the CNS having the same origin, termination, and function |  | 
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 | Definition 
 
        | bundle of neuronal processes (axons) outside the central nervous system |  | 
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 | Definition 
 
        | white substance of the central nervous system; the myelinated nerve fibers |  | 
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 | Definition 
 
        | the gray area of the central nervous system; contains unmyelinated nerve fibers and nerve cell bodies |  | 
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 | Definition 
 
        | (1) a peripheral nerve ending specialized for response to particular types of stimuli; (2)  molecule that binds specifically with other molecules, e.g., hormones and neurotransmitters |  | 
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 | Definition 
 
        | a receptor located in a muscle or tendon; concerned with locomotion, posture, and muscle tone |  | 
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 | Definition 
 
        | completes the pathway between afferent and efferent neurons; also called association neurons |  | 
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 | Definition 
 
        | the state of unstimulated neuron or muscle cell in which the inside of the cell is relatively negative in comparison to the outside; the resting state |  | 
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 | Definition 
 
        | the loss of a state of polarity; the loss of a negative charge inside the plasma membrane |  | 
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 | Definition 
 
        | a local change in membrane potential that varies directly with the strength of the stimulus, declines with distance |  | 
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 | Definition 
 
        | an electrical event occurring when a stimulus of sufficient intensity is applied to a neuron or muscle cell, allowing sodium ions to move into the cell and reverse the polarity |  | 
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        | a self propagating wave of depolarization; also called action potential |  | 
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 | Definition 
 
        | restoration of the membrane potential to the initial resting (polarized) state |  | 
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        | automatic reaction to a stimulus |  | 
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 | Definition 
 
        | neural pathway for reflexes |  | 
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 | Definition 
 
        | (1) discharging chambers of the heart (2) cavities within the brain
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 | Definition 
 
        | the largest part of the brain; consists of right and left cerebral hemispheres
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 | Definition 
 
        | a furrow on the brain, less deep than a fissure |  | 
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        | an outward fold of the surface of the cerebral cortex |  | 
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        | (1) a groove or cleft; (2) the deepest depressions or inward folds on the brain
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        | pertaining to the walls of a cavity |  | 
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 | Definition 
 
        | pertaining to area at the back of the head |  | 
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 | Definition 
 
        | an area of the central nervous system; contains unmyelinated nerve fibers and nerve cell bodies
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 | Definition 
 
        | substance of the CNS; the myelinated nerve fibers
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        | Term 
 
        | basal nuclei or
 basal ganglia
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        | gray matter areas deep within the white matter of the cerebral hemispheres |  | 
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 | Definition 
 
        | that part of the forebrain between the cerebral hemispheres and the midbrain including the thalamus, the third ventricle, and the hypothalamus |  | 
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 | Definition 
 
        | a mass of gray matter in the diencephalon of the brain |  | 
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 | Definition 
 
        | the region of the diencephalon forming the floor of the third ventricle of the brain |  | 
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 | Definition 
 
        | the neuroendocrine gland located beneath the brain that serves a variety of functions including regulation of the gonads, thyroid, adrenal cortex, water balance, and lactation |  | 
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 | Definition 
 
        | the portion of the brain consisting of the medulla, pons, and midbrain |  | 
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 | Definition 
 
        | the slender cavity of the midbrain that connects the third and fourth ventricles; also called the _________ of Sylvius |  | 
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        | (1) any bridgelike structure or part; (2) the brain area connecting the medulla with the midbrain, providing linkage between upper and lower levels of the CNS
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 | Definition 
 
        | part of the hindbrain; involved in producing smoothly coordinated skeletal muscle activity
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 | Definition 
 
        | the membranes that cover the brain and spinal cord |  | 
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 | Definition 
 
        | inflammation of the meninges of the brain or spinal cord |  | 
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 | Definition 
 
        | the outermost and toughest of the three membranes (meninges) covering the brain and spinal cord |  | 
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        | weblike; specifically, the weblike middle layer of the three meninges
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        | the fluid produced by choroid plexi; fills the ventricles and surrounds the CNS
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        | a mechanism that inhibits passage of materials from the blood into brain tissues |  | 
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 | Definition 
 
        | paralysis of one side of the body |  | 
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        | Term 
 
        | peripheral nervous system |  | Definition 
 
        | a system of nerves that connects the outlying parts of the body with the central nervous system |  | 
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 | Definition 
 
        | bundle of neuronal processes (axons) outside the CNS |  | 
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 | Definition 
 
        | a delicate connective tissue sheath that surrounds each fiber in a nerve |  | 
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 | Definition 
 
        | a bundle of nerve or muscle fibers bound together by connective tissue |  | 
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 | Definition 
 
        | a tough, fibrous sheath that binds together the fascicles in a nerve |  | 
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 | Definition 
 
        | nerves containing the processes of motor and sensory neurons; their impulses travel to and from the CNS
 |  | 
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 | Definition 
 
        | the 31 pairs of nerves that arise from the spinal cord |  | 
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 | Definition 
 
        | a network of interlacing nerves, blood vessels, or lymphatics |  | 
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 | Definition 
 
        | the division of the nervous system that functions involuntarily; innervates cardiac muscle, smooth muscle, and glands
 |  | 
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        | Term 
 
        | preganglionic (presynaptic) neuron |  | Definition 
 
        | a neuron of the autonomic nervous system having its cell body in the brain or spinal cord and its axon terminating in a ganglion |  | 
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        | Term 
 
        | postganglionic (postsynaptic) neuron |  | Definition 
 
        | a neuron of the autonomic nervous system having its cell body in a ganglion and its axon extending to an organ or tissue |  | 
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        | Term 
 | Definition 
 
        | a division of the autonomic nervous system; opposes parasympathetic functions;
 called the fight-or-flight division
 |  | 
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        | Term 
 | Definition 
 
        | a division of the autonomic nervous system; also referred to as the craniosacral division
 |  | 
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