The Nercous System and Behavior

Question Answer
addiction the state of being enslaved to a habit or practice or to something that is psychologically or physically habit-forming, as narcotics, to such an extent that its cessation causes severe trauma
axon .the appendage of the neuron that transmits impulses away from the cell body
behavior observable activity in a human or animal
brain the part of the central nervous system enclosed in the cranium of humans and other vertebrates, consisting of a soft, convoluted mass of gray and white matter and serving to control and coordinate the mental and physical actions
cell body the compact area of a nerve cell that constitutes the nucleus and surrounding cytoplasm, excluding the axons and dendrites
central nervous system the part of the nervous system comprising the brain and spinal cord
cerebellum a large portion of the brain, serving to coordinate voluntary movements, posture, and balance in humans, being in back of and below the cerebrum and consisting of two lateral lobes and a central lobe
cerebrum the anterior and largest part of the brain, consisting of two halves or hemispheres and serving to control voluntary movements and coordinate mental actions
conditioned reflex response learned response that results from the linding of two stimuli that repeatedly occur at the same time
dendrites the branching process of a neuron that conducts impulses toward the cell
depressant causing a lowering in spirits; dejecting.
effectors organ or cell that carries out a response to a nerve impulse
end brush an abundant, tuftlike branching at the axon ending of certain nerve cells
fatty sheath layer of fatlike material aroind the axon of a nerve cell
ganglions a mass of nerve tissue existing outside the central nervous system
habit an acquired behavior pattern regularly followed until it has become almost involuntary
hallucinations a sensory experience of something that does not exist outside the mind, caused by various physical and mental disorders, or by reaction to certain toxic substances, and usually manifested as visual or auditory images
hallucinogens a substance that produces hallucinations
impulses the product of the average force acting upon a body and the time during which it acts, equivalent to the change in the momentum of the body produced by such a force
instinct an inborn pattern of activity or tendency to action common to a given biological species
medulla oblongata the lowest or hindmost part of the brain, continuous with the spinal cord.
meninges the three membranes covering the brain and spinal cord
narcotics any of a class of substances that blunt the senses, as opium, morphine, belladonna, and alcohol, that in large quantities produce euphoria, stupor, or coma, that when used constantly can cause habituation or addiction
nerve one or more bundles of fibers forming part of a system that conveys impulses of sensation, motion, etc., between the brain or spinal cord and other parts of the body
nerve cell a specialized, impulse-conducting cell that is the functional unit of the nervous system, consisting of the cell body and its processes, the axon and dendrites
nervous system the system of nerves and nerve centers in an animal or human, including the brain, spinal cord, nerves, and ganglia
peripheral nervous system the portion of the nervous system lying outside the brain and spinal cord
receptors any of various specific protein molecules in surface membranes of cells and organelles to which complementary molecules, as hormones, neurotransmitters, antigens, or antibodies, may become bound
reflex noting or pertaining to an involuntary response to a stimulus, the nerve impulse from a receptor being transmitted inward to a nerve center that in turn transmits it outward to an effector
reflex arc the nerve pathways followed by an impulse during a reflex
responses and sympathetically to appeals, efforts, influences, etc
simple reflex act rapid, inborn, beneficial response to a stimulus
spinal cord the cord of nerve tissue extending through the spinal canal of the spinal column
stimulant any food or beverage that stimulates, esp. coffee, tea, or, in its initial effect, alcoholic liquor
stimuli changes in the environment of an organism that cause it to react
synapse a region where nerve impulses are transmitted and received, encompassing the axon terminal of a neuron that releases neurotransmitters in response to an impulse, an extremely small gap across which the neurotransmitters travel
taxis oriented movement of a motile organism in response to an external stimulus, as toward or away from light
tropism an orientation of an organism to an external stimulus, as light, esp. by growth rather than by movement
voluntary act controlled by will