Across
- 2. a cell within the nervous system that carries electrical impulses
- 7. a rapid change in charge that causes a propagated nerve impulse
- 8. the period where resting potential re-established
- 12. electrical signal that travels along the axon of a neuron
- 13. is a neurotransmitter with both excitatory and inhibitory actions
- 16. the minimum membrane potential (roughly -55 mV) required to fire an action potential
- 17. gaps between the Schwann cells myelin sheaths
- 19. the type of cell that produces the myelin sheath around axons
- 20. the positive ion that influxes into the axon during depolarization
- 21. refers to a sudden change in membrane potential
- 22. junctions between neurons or between neurons and receptor/effector cells
Down
- 1. a chemical messenger released into the synaptic cleft to transmit signals
- 3. the maintenance of a difference in charge (polarity) across a neuron's membrane
- 4. a short, branched extension of a neuron that carries impulses toward the cell body
- 5. the difference in electrical charge or voltage across a plasma membrane
- 6. "skipping" of impulses
- 9. sheaths an insulating layer around axons
- 10. the enzyme that breaks down acetylcholine in the synaptic cleft
- 11. ion that enters the presynaptic neuron to trigger the release of neurotransmitters
- 14. a long, single nerve fiber that conducts electrical impulses away from the cell body
- 15. the positive ion that effluxes out of the axon during repolarization
- 18. the membrane potential of a neuron when it is not firing (roughly -70 mV)