Autonomic Nervous System (ANS)-Consists of visceral nerve fibers that regulate activity of smooth muscle, cardiac muscle, and glands. (A.K.A.- Involuntary Nervous System)
Functions; Support and brace neuron, guide migration of young neurons, control chemical environment. Plays role in exchange between capillaries and neurons (Most important)
Schwann Cells (Neurolemocytes)-Surround all perepheral nerve fibers and form myelin sheaths in thick nerve fibers. (Similar to oligodendrocytes in CNS)
Rough ER-Chromatophilic substance
Neurofibrils-bundles of intermediate filaments (neurofilaments). Maintains shape and integrity.
Nuclei-Clusters of cell bodies in CNS
Ganglia-Lie along nerves in PNS
2 Types; Dendrites-main receptive or input regions. Many!
Axons-only one! Conducting region.
Nerve Fiber-Any long axon
Axon Collaterals-Extend from axon at (more or less) right angles.
Terminal Branches-many branches at end of axon.
Axon Terminals/Boutons-Knoblike distal endings of the terminal branches.
Postsynaptic potential-stimulus is neurotransmitter released by another neuron.
Brief reversal of membrane potential
#2 Depolarization- Na+ channels open
#3 Repolarization- Na+ channel are inactivated and K+ channels open.
#4 Hyperpolarization- Some K+ channels remain open, and Na+ channels reset