E1 Ch 5 Vocab Flashcards
depolarization
occurs when membrane potential becomes less negative than the resting membrane potential. Is excitatory and increases the likelihood of the creation/propagation of an action potential
modulation
gradual and longer lasting changes in membrane potential.
hyperpolarization
when a membrane potential becomes more negative than the resting membrane potential. Is inhibitory and decreases the likelihood of the generation/propagation of an action potential
summation
the process of combining multiple ESPS in the axon hillock of a neuron b/c a single ESPS is not enough to reach the needed threshold level
temporal summation
the repeating, rapid succession of a stimuli at the same synapse. The rapid succession works together to build up the necessary threshold level
spatial summation
stimuli is firing at multiple synapses of one neuron at the same time. The combined effort then works to reach the threshold level
nodes of ranvier
small patches along the axon that remain unmyelinated
Interneuron
largest class of neurons and act throughout the nervous system. works locally or at a distance
convergence
process by which multiple inputs from a lot of cells terminate on a single neuron cell
divergence
process by which a single neuron may have many branches that terminate on many other cells
leak channels
allow diffusion of a small number of ions through the cell membrane at a slow continuous rate. key to maintain osmotic gradients
modality-gated channels
keyed to specific sensory neurons. open in response to mechanical forces (touch, stretch, pressure), chemical changes, temperature changes
ligand-gated channels
open in response to neurotransmitters binding
voltage-gated channels
open in response to changes in electrical potentials across cell membrane. Open and close very fast. key to propagation of action potentials and release of neurotransmitters
