Transcript Nervous System

Nervous System
Nervous System - Functions
- Collects information about the body’s internal and
external environment
- Regulates organs
- Regulates behavior
- Controls sensory and motor functions
- Maintains homeostasis
Major Components
· Central Nervous System (CNS)
· Brain and spinal cord
· Peripheral Nervous System (PNS)
· Sensory neurons
· Motor neurons
Main Parts-CNS
· Brain
· Control center
· Processes and relays
information
· Spinal Cord
· Main communication link
between brain and rest of
the body
Decision Making
Coordination of
Movement
Main Parts-PNS
· Sensory Neurons
· Transmit information about environment to the
brain
· Motor Neurons
· Transmit impulse from the brain to muscles
Basic Unit = Neuron
· Dendrites
· Receive electrical signal
· Body
· Signal is then sent to this central region
· Axon
· The signal is carried through this to the synapse
· Synapse
· Junction between the axon of one neuron and the
dendrites of another
dendrites
synapse
cell body
synapse
axon
synapse
NEURON
How the CNS and PNS work together:
---------------PNS------------ ---------CNS------
Neuron Function
To transmit signals from one neuron to another
•Dependent upon electrical activity
•Electrical charges of the neuron and its
surroundings differ
•This creates a “potential”
•RESTING POTENTIAL
•Not receiving or transmitting a signal
•ACTION POTENTIAL
•Receiving or transmitting a signal
---electric message---chemical
---electric message----
message
Checking:
1. What two organs make up the central nervous
system?
a. ________________ b.______________
2. What is the difference between sensory neurons and
motor neurons?
a. Sensory neurons bring impulses to the ________.
b. __________ neurons bring impulses to
___________, ______________ or
_____________.
3. A neuron at ________________ potential is not
sending a signal.
4. What is the nature of the signal transmitted in the
space BETWEEN two neurons?
A. Electrical B. Chemical C. Refractory
Pass it along!