| A | B |
|---|
| 90% of our neurons are ___________ that lie completely within the central nervous system. | interneurons |
| ________ or _____ neurons conduct signals away from the central nervous system. | Efferent motor |
| A collection of cell bodies in the peripheral nervous system is called a ________. | ganglion |
| Rough ER and ribosomes are clustered into _____ ______, dark-staining regions in the soma of the neuron. | Nissl bodies |
| The mound or thickened region of the soma where the axon originates is called the ____ _______. | axon hillock |
| The most common structural type of neuron is the __________ neuron, which has many dendrites and a single axon. | multipolar |
| __________ axonal transport involves movement of substances toward the soma. | Retrograde |
| Slow axonal transport, also called axoplasmic flow, is always ___________ in direction. | anterograde |
| The outermost layer of the myelin sheath on a peripheral nerve fiber is called the __________ and contains the nucleus and most of the cytoplasm of the Schwann cell. | neurilemma |
| If threshold is reached, and an action potential is triggered, the voltage-gated sodium channels open and sodium rushes into the axon. This rapid shift in the membrane potential is called ______________. | depolarization |
| During an action potential, the K+ gates stay open longer than the Na+ gates, and so more K+ leaves than Na+ enters the axon. This creates a membrane potential that is more negative than the original resting membrane potential. This negative overshoot is called _______________ and is responsible for the relative refractory period. | hyperpolarization |
| Impulse conduction in myelinated nerve fibers is called _________ conduction. | saltatory |
| Most synapses between neurons are chemical. Strictly electrical synapses do exist and are called ___ _________. | gap junctions |
| Acetylcholine is a neurotransmitter that can have either excitatory or inhibitory effects depending upon the type of receptors on the _____________ ________ . | postsynaptic membrane |
| A neuron may receive thousands of EPSP's and IPSP's at once. Integration of these post-synaptic potentials to determine whether threshold has been reached is called _________. | summation |
| Name the three fundamental types of neurons | Afferent; Interneuron or association; Efferent or motor neurons |
| Name three properties of neurons. | Excitability; Conductivity; Secretion |
| Identify two factors that determine the speed of nerve signal transmission. | Diameter of fiber - larger fibers are faster; Presence of myelin - myelinated fibers are faster |
| Name the three major categories of neurotransmitters. | Acetylcholine; Amino acid neurotransmitters; Monoamines - includes catecholamines |
| Name the 6 types of neuroglial cells | Schwann cells; Satellite cells; Oligodendrocytes; Astrocytes; Ependymal cells; Microglia |
