Chapter 10 Flashcards
nervous system
nervous system
coordinates and controls all bodily activities; nerves, brain, spinal cord and sensory organs
central nervous system
brain and spinal cord, receives and processes information and regulate all bodily activity
peripheral nervous system
12 pairs of cranial nerves extending from brain and 31 pairs of peripheral spinal nerves from the spine cord, transmit never signals to and from the central nervous system
nerve
one or more bundles of neurons that connect brain and spinal cord with other parts of the body
tract
bundle or group of nerve fibers located within the brain and spinal cord
ascending nerve tract
carry nerve impulses toward the brain
descending nerve tract
carry nerve impulses away from the brain
ganglion
nerve center made up a cluster of nerve cell bodies outside the central nervous system
innervation
supply of nerves to a specific body part
plexus
network of intersecting spinal nerves
receptors
sites in sensory organ that receive external stimulation, send stimulus through sensory neurons to brain for interpretation
stimulus
anything that excites a nerve and causes an impulse
impulse
wave of excitation transmitted through nerve fibers and neurons
reflex
an automatic, involuntary response to some change either inside or outside the body
neurons
basic cells of nervous system that allow different parts of the body to communicate
brain waves
process that creates patterns of neuron electrical activity in the brain
dendrites
root-like processes that receive impulses and conduct them to the cell body
axon
process that conducts impulses away from the nerve cell
terminal end fibers
branching fibers at the end of an axon that lead nerve impulse form icon to synapse
synapse
space between two neurons or between a neuron and a receptor organ
neurotransmitters
chemical substance that make it possible for messages to cross from synapse of the neurons to the target receptor
glial cells
provide support and protection for neurons, hold the neurons in place, supply nutrients and oxygen, insulation, destroy and remove dead neurons
myelin sheath
protective covering made up of glial cells
white matter
portion of nerve fibers that are myelinated