3-30. THE NERVOUS SYSTEM
The nervous system may be sub classified as the central nervous system and
the peripheral nervous system. The central nervous system includes the brain and
spinal cord, while the peripheral nervous system includes all the nerves, ganglia, and
end organs connecting the central nervous system with all other parts of the body. The
peripheral nervous system includes the 12 pairs of cranial nerves (figure 3-17), the 31
pairs of spinal nerves, and the sympathetic nervous system.
Figure 3-17. The human brain (basal surface showing cranial nerves).