| Term | Definition |
|---|
| central nervous system (cns) | includes the brain and spinal cord,which occupy a midline or central location in the body |
| peripheral nervous system(pns) | nerves outside of the cna constitute the pns |
| sensory | detects enviromental stimuls (internal or external) sends that info to cns for response,reaction or reflexes |
| autonomics nervous system | includes nerves that control structures automatically or involuntary. |
| somatic nervous system | includes nerves that voluntarily (conscious)control skeletal muscle fibers |
| neurons | conduct impluses (electric signals) |
| receptor | impulses begin at the sensor or |
| dendrite | there are ends of neurons |
| cell body | dendrites convey the impulses to where the nuclues is |
| axon | nerve cell process that transmites impulses away from the cell body |
| schwann cells | large nucleated cells that form myelin |
| myelin sheath | cell membranes that are wrap around the axon many times with their cell membranes |
| white matter | areas of the nervous system with myelin are called |
| nodes of Ranvier | neuron spaces between the myelin sheaths are called |
| Multiple Sclerosis | where white blood cells attack the myelin, mistaking it for a similar virus |
| sensory,or afferent neurons | transmit impulses toward the cns |
| motor, or efferent neurons | transmit impulses away from the cns |
| nerves | bundles of neurons, axons in the pns form |
| tracts | bundles of neurons in the cns form |
| neuroglia | support, nourish and protect neurons |
| astrocytes | attach to neurons and to small blood vessels |
| blood brain barrier | they control the nutrients taken from the blood and given to the neurons |
| microglia | are smaller white blood cells born and bred in the NS where they recognize the antigens on neurons |
| oligodendrocytes | the cells in the cns that produce multiple myelin sheaths for multiple numbers of neurons |
| glioma's | they are th source of ns cancers |
| neuron pathways | trillions of routes that impulses can cover are called |
| fibers | long portion of neurons are called |
| posterior (dorsal) root | just before the spinal cord, the sensory dendrites split into the |
| posterior (dorsal) root ganglion | sensory cell bodies are located in the |
| ganglion | a group of nerve cell bodies located in the pns |
| interneurons | tiny non myelinated neurons found in the gray matter of the spinal cord |
| synaptic cleft | nerve impulse stops at a space that separates the sensory axon from the dendrites of the motor neuron |
| synapse | is the meeting between a neuron and an effector |
| effector | is a structure that will put the nerve signal "into effect" |
| anterior (ventral) root | the motor neuron axon leaves the anterior spinal cord gray matter and joins the nerve |
| reflex | the response to impulse conduction over reflex arc is called |
| stretch reflex | a sensory neuron alerts a motor neuron to tell the quadriceps to contract, or shorten this is called |
| withdraw reflex | puttin your finger on a stove implements another reflex arc called |
| nerve impluse | self propagating wave of electrical disturbance that travels along the surface of a neuron's plasma membrane |
| action petentials | nerve impulses are also know as |
| saltatory conduction | if the traveling impulse encounters a section of membrane covered with myelin, it "jumps" the myelin and actually speeds up the conduction |
| presynaptic neuron | neuron before the synapse is called |
| postsynaptic neuron | neuron after the synapse is called |
| synaptic knobs | presynaptic neurons axons terminate in bulges where chemicals are stored inside called |
| vesicles | chemical inside the knobs are enclosed in sacs called |
| neurotransmitters | the chemicals are called |
| acetylcholine | is released at neuromuscular junctions and excites skeletal muscle cells to contract |
| endorphins and inkephalins | are released at brain and spinal cord synapses in the pain conduction pathway |
| brain stem | is the lowest part of the brain and includes in order above the spinal cord: the medulla, pons and midbrain |
| reticular formation | all three have an area that determines the alertness level of the brain |
Combine with other sets
Share on Facebook
Share on MySpace