Nervous System Flashcards
Sensory (afferent)
functional- receive sensory information from receptors that detect stimuli and transmit info to CNS
Motor (efferent)
functional- initiate and transmit motor output from CNS to effectors- controls tissue and glands
Association
Functional- receive, process, and store information and “decide” how to respond
Multipolar
Structural- skeletal/motor and interneurons (most)
Unipolar
Structural- sensory
Bipolar
Structural- sensory- olfactory epithelium of nose and retina of eye
Astrocytes
CNS- start from capillary and attach to neuron; help form blood-brain barrier
Microglia
CNS- defend against bacteria/ infection; engulf debris, dead/dying neurons (act as lysosome)
Oligodendrocyte
CNS- wraps around (like myelinated axon); allows faster action potential conduction
Ependymal cell
CNS- assist in production of cerebral spinal fluid; line brain
Schwann cell (neurolemmocyte)
PNS- wraps around axon like a jelly roll; allow faster action potential conduction
Satellite cells
PNS- regulate nutrients and waste
Action potential
self-propogating change in membrane potential occurring in excitable cells
Axon terminal
telodendria- fine terminal extensions formed from axon and collateral branches at distal end
Depolarization
making membrane more positive; change in membrane potential or voltage to a more positive value
excitatory postsynaptic potential
EPSP- Sodium in and Potassium out resulting in a temporary less negative state across the membrane
hyperpolarization
change in the membrane potential to a value more negative than the resting potential
inhibitory postsynaptic potential
IPSP- potassium out and chlorine in resulting in a temporary more negative state
local potential (postsynaptic potential)
graded potentials that occur in post synaptic neurons; graded potentials occur in the receptive segment of a neuron due to opening of chemically gated channels
neurotransmitter
chemical messenger; chemical released from a neuron that delivers information to another cell
postsynaptic neuron
distal side of a synaptic cleft; signal receiver or target
presynaptic neuron
proximal side of a synaptic cleft; signal producer
repolarization
change in membrane potential from a depolarized value back to the resting value
resting membrane potential
RMP- voltage measured across the plasma membrane of an excitable cell at rest