1. 1. THE NERVOUS SYSTEM 2. THE NEURON 3. THE PERIPHERAL NERVOUS SYSTEM 4. THE CENTRAL NERVOUS SYSTEM

2.  THIS SYSTEM HELPS COORDINATE ALL THE BODIES ACTIVITIES SO THEY WORK IN HARMONY  IT RECEIVES, PROCESSES, STORES, AND TRANSMITS INFORMATION FROM BOTH INSIDE AND OUTSIDE THE BODY  CENTRAL SYSTEM: - BRAIN - SPINAL CORD  PERIPHERAL SYSTEM: - NERVES - SENSORY RECEPTORS

3.  100 BILLION NEURONS (ON AVERAGE)  ALSO CALLED “NERVE CELLS”  IT IS A SPECIALIZED NERVE CELL IN THE NERVOUS SYSTEM THAT RECEIVES AND TRANSMITS MESSAGES  MADE UP OF 4 PARTS - DENDRITES - CELL BODY (which contains the nucleus) - AXON - AXON TERMINALS

4.  ROLE OF NEURONS: 1. TO PICK UP STIMULI 2. TRANSFORM THEM INTO NERVE IMPULSES 3. TRANSMIT THESE IMPULSES  STIMULUS: anything that can be perceived by a living organism and that can trigger a reaction. Sound, light, heat, electrical shocks, odours, hormones are all examples of stimuli.  NERVE IMPULSE: an electrical signal transmitted by a neuron  SYNAPSE: the transition zone between two neurons that allows a nerve impulse to be transmitted  NERVE: a structure that helps transmit information between the central nervous system and various regions of the body

5.  CHARACTERISTICS 1. CAN BE STIMULATED: IT REACTS TO A STIMULUS BY CHANGING INTO AN ELECTRICAL SIGNAL (NERVE IMPULSE) 2. CONDUCTIVE. TRANSMITS NERVE IMPULSE FROM NEURON TO ANOTHER UNTIL IT REACHES TARGET 3. CONSUMES A GREAT DEAL OF OXYGEN AND GLUCOSE. CAN ONLY SURVIVE A FEW MINUTES WITHOUT OXYGEN 4. CAN LIVE MORE THAN 100 YEARS. PEOPLE KEEP THE SAME NEURONS THEIR ENTIRE LIFE 5. CANNOT REPRODUCE ITSELF, CANNOT BE REPLACED IF DESTROYED  TRANSMISSION OF NERVE IMPULSES 1. DENDRITES OF A NEURON RECEIVE MESSAGES OR STIMULI AND TRANSFORM THEM INTO NERVE IMPULSES 2. THE NERVE IMPULSES ARE THEN TRANSMITTED ALONG AXONS TO THE AXON TERMINALS 3. NERVE IMPULSES TRAVEL FROM ONE NEURON TO ANOTHER VIA NEUROTRANSMITTERS SECRETED BY AXON TERMINALS ACROSS A NARROW SPACE OR TRANSMISSION ZONE (SYNAPSE), BETWEEN TWO NEURONS.

6.  CONNECTS DIFFERENT PARTS OF THE BODY TO THE CENTRAL NERVOUS SYSTEM  INTERNAL/EXTERNAL MESSAGES  SENSORY RECEPTORS: PICK UP STIMULI AND TRANSFORMS THEM INTO NERVE IMPULSES  2 TYPES OF NERVES: sensory and motor SENSORY NERVES: (5 SENSES + OTHERS) - TRANSMIT INFORMATION, THE FORM OF NERVE IMPULSES FROM THE SENSORY RECEPTORS TO THE CENTRAL NERVOUS SYSTEM MOTOR NERVES:(MUSCLES + OTHERS) - TRANMSIT IMPULSES FROM THE CENTRAL NERVOUS SYSTEM TO THE MUSCLES IN ORDER TO PRODUCE VOLUNTARY AND INVOLUNTARY MOVEMENTS

7.  BRAIN: composed of the parts of the central nervous system located in the cranium - CEREBRUM - CEREBELLUM - BRAIN STEM SPINAL CORD : the nervous system organ that carries information from/to the various parts of the body to/from the brain. It is also the reflex center - SPINAL NERVES - VERTABRAE

8.  COMMAND CENTER FOR ALL - VOLUNTARY MOVEMENTS - INTERPRETATION OF THE SENSES - INTELLIGENCE - CENTER FOR EMOTIONS  DIVIDED INTO TWO HEMISPHERES (RIGHT / LEFT) - RIGHT: CONTROLS THE LEFT SIDE OF THE BODY - LEFT: CONTROLS THE RIGHT SIDE OF THE BODY  OUTER LAYER – CEREBRAL CORTEX (GREY MATTER) - Muscle control, sensory perception, memory, speech  INNER LAYER – WHITE MATTER - System connectedness

9. FUNCTIONDESCRIPTIONEXAMPLE CONTROLS VOLUNTARY MOVEMENTS MOTOR CONTROL SENDS OUT NERVE IMPULSE TO STIMULATE MUSCLES TO CONTRACT -Stretching -Muscle use -Walking -Grasping INTERPRETS MESSAGES PICKED UP BY SENSES WHEN SENSES DETECT EXTERNAL STIMULUS THIS REGION INTERPRETS IMPULSE AND REACTS -Tactile reaction -Smelling -Reaction to light CONTROLS INTELLIGENCEPROBLEM SOLVING, READING, REASONING:ANY ACTIVITY ASSOCIATED WITH INTELLIGENCE -Thinking -Reflection -Reasoning CONTROLS EMOTIONSMANAGES EMOTIONS JOY, SAD, FEAR, ANGER, ETC -Laughing -Crying REGULATES PHYSIOLOGICAL FUNCTIONS HYPOTHALAMUS IS RESPONSIBLE FOR HUNGER, THIRST, ALERTNESS AND TEMPERATURE REGULATION. ALSO CONTROLS THE PITUITARY GLAND -hot/cold -Consciousness -Sweating

10.  THE CENTER FOR BALANCE AND MOVEMENT COORDINATION EXAMPLES:  POSTURE  DANCE, RUN  MOTION SICKNESS, VERTIGO  SPEAK  DEXTERITY (PLAY PIANO)

11.  THE CONTROL CENTER OF INTERNAL STIMULI AS WELL AS INVOLUNTARY MOVEMENT EXAMPLES:  INTERNAL MUSCLES (DIGESTIVE SYSTEM)  TWITCHING  SPASMS  RESPIRATION  BLINKING

12.  NERVOUS SYSTEM ORGAN THAT CARRIES INFORMATION FROM THE VARIOUS PARTS OF THE BODY TO THE BRAIN (AND VISE VERSA).  THE REFLEX CENTER  PROTECTED BY VERTEBRAE (BACK BONE)  REFLEX: A RAPID AND INVOLUNTARY RECTION TO A STIMULUS (GOOSE BUMPS)  REFLEX ARC: PATH TAKEN BY A NERVE IMPULSE DURING A RELFEX