Nervous System-Chapter 44 Flashcards
detect stimulus, photoreceptors, chemoreceptors
sensory receptors
respond to stimuli, muscles, gland
motor effectors
brain and spinal cord
central nervous system
sensory and motor neurons
peripheral nervous system
carry impulse to the CNS
sensory neurons
carry impulses from CNS to effectors
motor neurons
provide more complex reflexes and associative functions, majority of neurons
interneurons
enlarged part containing nucleus
cell body
short, cytoplasmic extensions that receive stimuli
dendrites
single, long extension that conducts impulses away from cell body
axon
multiple layers of cell membranes wrapped around axons
myelin sheath
myelinated axons in CNS form _____, form _________ in PNS
white matter, nerves
resting, depolarization, repolarization, hyperpolarization
steps of an action potential
neurotransmitters activate ____________ on the postsynaptic cell
ligand-gated ion channels
bind to ligand-gated ion channel, new AP begins on the postsynaptic cell, action terminated by enzymatic breakdown or cellular reuptake
neurotransmitter