Section 2: Nervous System, Spinal Nerve Organization, Autonomic Nervous System

- receiving and processing internal and external env impulses - initiating an appropriate response - also involved in integration of signals

1) Structurally 2) Functionally

1) CNS - brain, spinal cord which are inside the skull and vertebral canal (therefore protected by bony cavities) 2)PNS - including spinal and cranial nerves and plexuses - some parts are inside vertebral canal (ie. vertebral foramen)

- network of nerve fibres

1) Somatic - innervates skin and skeletal muscles - mainly involved w/receiving and responding to information from the external env 2) Visceral - innervates organ systems in the body and other visceral elements such as smooth muscles and glands in peripheral regions - detecting and responding to information from the internal env

- sensory - passing information of stimulus from periphery to nervous system

- motor - responding to the information by sending signals from nervous system to periphery

- related to autonomic system - combination of CNS and PNS (centres of autonomic sys in CNS, PNS sends msgs) - can be classified as having both somatic and visceral functionalities

- myelinated processes - myelinated nerve fibers (phospholipids bring about white colour

- nerve cell bodies - bundles of unmyelinated nerve fibers and neuroglia - in spinal cord, forms H-shaped inner core surrounded by white matter - in brain and cerebellum, thin outer shell of gray matter overs cortex

- clugsters of cell bodies w/in CNS - gathering site of cell bodies of neurons in CNS - also sites of nerve synapses - sensory/motor/autonomic

- aggregations of cell bodies outside the CNS - gathering site of cell body of neurons in PNS - also site of nerve synpases - sensory/autnomic

- in the periphery of the brain and cerebellum - where the cell bodies of neurons are found (gray matter)

1) cerebrum 2) brainstem 3) cerebellum

- highly convoluted structure - composed of two massive cerebral hemispheres (right and left) and the diencephalon - gyri and sucli