nerves and action potentials Flashcards
dendrite
collection site of the neuron; input; signal moves towards the soma
soma
integration; center of the neuron, houses the nucleus
axon
conduction; signal moves away from the soma
axon terminal
transmission
axon hillock
location where the axon meets the soma; where action potentials are generated
glial cells
neuron support cells, provide metabolic and structural support
Schwann cells
glial cells that provide a myelinated sheath to speed up signal transmission; found in the peripheral nervous system
oligidendrocytes
glial cells that provide a myelinated sheath to speed up signal transmission; found in the central nervous system
astrocytes
glial cells that line capillaries and serve as metabolic intermediates
neuronal circuit
signal>sensory neurons>interneurons or motor neurons>effector
sensory neurons
step in the neuronal circuit that decide on action potentials; afferent fibers
interneurons
step in the neuronal circuit that links in the central nervous system; send signals out
motor neurons
step in the neuronal circuit that signals muscle movement; efferent fibers
afferent fibers
signals coming in
efferent fibers
signals going out
polarized cell
has electrical potential; resting state
depolarized cell
moving from negative to less negative due to some potential
repolarized cell
returning to resting polarized state after a potential
hyperpolarization
period of becoming too negative to overcompensate for an action potential
graded potential
graded response, initial disturbance dies with distance or time, can be summed, no threshold, no refractory period, duration and intensity varies, can be de or hyper polarizing, initiated by stimulus, or spontaneously
Action potential
all or nothing response, can be regeneratively propagated, cant be summed, requires a threshold to be met, refractory period, duration is constant, only depolarizing, only initiated by membrane depolarization
passive electrical resting potential
capacitance and resistance occurring across the cell membrane
active electrical resting potential
voltage gated channels allow rapid depolarization
capacitance
the ability to hold a charge and resist change