1) Organization of the Nervous System

Components of CNS

Brain and spinal cord

Function of CNS

integrates information received from the PNS (peripheral nervous system) and coordinates and influences the activity of all parts of the body.

Components of PNS

31 pairs of spinal nerves and their branches, 12 pairs of cranial nerves and their brances, plexuses, and ganglia

Function of PNS

Provides information to the CNSS about internal and external environment

What 2 nervous systems is the PNS divided into?

somatic and automatic nervous systems

What is white matter composed of (2)

mostly myelinated axons

What is grey matter composed of? (4)

neuronal cell bodies, dendrites, unmyelinated axons, and neuroglia.

Pattern of grey and white matter in spinal cord

central cavity surrounded by gray matter and then white matter surrounding that

Pattern of grey and white matter in brain

similar to spinal cord but additional scattered gray matter within the white matter AND the cerebrum and cerebellum also have an outer layer of gray matter called the cortex

ganglion definition

a cluster of neuron cell bodies (somas) and dendrites located outside the CNS

nucleus defintion

a cluster of neuronal cell bodies located deep within the CNS

nerve definition

cord-like bundle of nerve fibers (called axons) that serves as a communication pathway in the PNS

Tract definition

a bundle of parallel nerve fibers (axons) located entirely within the CNS that share a common origin, destination, and function