FUNCTION: Reacts to the environment.
Get and interpret information about the body's internal and external environment,
Helps maintain homeostasis.
Stimulus and Response.
Telephone communication system.
Central Nervous System. Includes brain (control center) & spinal cord.
PNS: Periphal Nervous System. Nerves of the body, neuron transmitters.
Go to the CNS.
pairs; 12 cranial and 32 spinal nerves.
Autonomic- involuntary system.
Works the organs and glands.
Sympathetic- speed up
Somatic- voluntary system. Works the peripheral muscles.
Sensory:carries messages to the brain for a decision.
Gets the info from sense organs (eyes, nose, ears, tongue and skin).
Motor: carries messages from brain and spinal cord to the muscle or gland.
* association - connects the sensory and
motor neurons together in the brain and spinal cord.
Neurons: nerve cell
Dendries: many thread-like fibers that bring messages into the cell.
Axon: one large fiber that sends messages away from the cell body to the next
Synapse: space where messages crosss over from one cell to the next.
Myalin Sheath: surrounds axon for protection and insulation.
with Myalin sheath messages go quicker