1. Nervous System and The Brain

4. The Nervous System Subdivided into two categories:
Central Nervous System
Contains brain and spinal cord
Peripheral Nervous System
Nerves and ganglia outside of CNS
Reflexes
A hot stove

8. The Nervous System
The nervous system has a coordinating role where it receives, processes, stores, and transmits information that comes from the body and the outside world
The neuron is the basic unit (cell) of the nervous system
Impulses (signals) are carried throught the body by nerves

9. Neurons Dendrite receives impulses Axon propagates the impulses
Longest neuron in the body? Sciatic nerve which connects toes to spinal cord

10. Neurons The neurons are the only cells that react to a stimulus
A stimulus is a change in the environment that results in nerve excitation
Ex. sun shining in your eyes or hearing a sound
Nerves are structures that help transmit information between the central nervous system and the various regions of the body

12. Transmitting Signals
Neurons must pick up stimuli, transform them into nerve impulses and then transmit these impulses on to the next neuron
A nerve impulse is therefore any electric signal transmitted by a neuron
As signals move from one neuron to another, they must cross the synapse. This is the transition zone between two neurons (a very small gap)

13. Basic Tasks of the Nervous System
Sensory Input: Monitor both external and internal environments.
Integration: Process the information and often integrate it with stored information.
Motor output: If necessary, signal effector organs to make an appropriate response.