Neurons

6. change from a negative to a positive charge of a nerve cell
7. small fluid-filled gap between neurons through
8. tube-like part of a neuron that carries messages away from the cell body toward other neurons
9. protective insulation that covers the axons of certain neurons
11. nerve cells that handle the information-processing function
14. structures at the end of axons that receive neural impulses
16. a stable negative charge of an inactive neuron
17. temporary state in which a neuron is unable to fire in response to continued stimulation
18. mass of nerve tissue encased in the skull
20. nerve cells within the central nervous system that process information
22. a positive shift in the electrical charge in the neuron’s resting potential, making it less negatively charged

1. disease in which the myelin sheath that insulates axons is damaged
2. an atom or a molecule in which the total number of electrons is not equal to the total number of protons
3. organs or structures that produce secretions called hormones
4. chemical messengers that transport nerve impulses
5. neurons which transmit information from sensory organs, muscles, and inner organs to the spinal cord and brain
10. a bundle of axons from different neurons that transmit nerve impulses
11. Gaps in the myelin sheath that create noninsulated areas along the axon
12. cells in the nervous system that support neurons and that form the myelin sheath found on many axons
13. a secretion from endocrine glands that help regulate bodily processes
15. swellings at the tips of axons from which neurotransmitters are dispatched into the synapse
19. convey nerve impulses from the central nervous system to muscles and glands
21. cell body of a neuron that contains the nucleus of the cell and carries out the cell’s metabolic functions