Transcript The Nervous System

The Nervous System
• The NERVOUS
SYSTEM controls
and coordinates
functions
throughout the
body and responds
to internal and
external stimuli
NEURONS are cells that transmit
messages, called IMPULSES,
through the nervous system
The CELL BODY contains the
NUCLEUS and most of the cytoplasm,
metabolic activity of the cell takes place
here
DENDRITES branch out from the cell body, and
they carry impulses from the environment or from
other neurons toward the cell body
The AXON carries impulses away from the cell
body.
The Nervous System can be
broken into two parts:
• The CENTRAL NERVOUS SYSTEM:
composed of the brain and the spinal
cord
• The PERIPHERAL NERVOUS
SYSTEM: composed of all the nerves
that aren’t part of the brain or spinal
cord
Central Nervous System
• The skull and vertebral column protect the
brain and spinal cord
The Spinal Cord
• Communication line
between the brain and
the rest of the body
• Made up of bundles of
nerves that branch out
into the rest of the body
Peripheral Nervous System
• SENSORY DIVISION
transmits impulses
from the sense
organs to the brain
• MOTOR DIVISION
transmits impulses
from the brain to the
muscles or glands
Peripheral Nervous System
• SOMATIC –
regulates voluntary
impulses
• AUTONOMIC regulates the
involuntary body
functions