The document summarizes the key aspects of the human nervous system. It describes how the nervous system and endocrine system both play a role in homeostasis through secreting chemical messages, though the nervous system is much faster. It defines the main cell type, neurons, and describes the three types - sensory, inter, and motor neurons. It also outlines the main components of the central nervous system, including the brain and spinal cord, and the peripheral nervous system. Finally, it briefly discusses some common malfunctions of the nervous system like cerebral palsy, meningitis, stroke, and polio.

1. The Nervous System