2. THE NERVOUS SYSTEM HOW DOES IT WORK?

3. Function of the Nervous System  Controls and coordinates functions throughout the body  How?  By responding to external and internal stimuli!  List 3 external (outside the body) stimuli:  Temperature  Texture  Brightness  List 2 internal (inside the body) stimuli:  Heart rate  Peristalsis

4. Neurons  Special cell that transmits impulses  3 TYPES  Sensory  From sense organs (eyes, nose, skin, ears, tongue) to brain/spinal cord  Motor  From brain/spinal cord to muscles/glands  Interneurons  Interconnect other two types  Found in brain and spinal cord http://www.rainbowstudio.com

5. Parts of a Neuron

6. The Synapse Impulses are transmitted from one neuron to the nextImpulses are transmitted from one neuron to the next Synapse:Synapse: –The space between neurons where impulses “jump” from one neuron to the next Neurotransmitters:Neurotransmitters: –Chemicals used to help transfer the impulse across the synapse –Found in tiny sacs (vesicles) at the axon terminals –Released from vesicles by the impulse reaching the axon terminals

7. The Synapse

8. The Nervous System How is it made up?

9. Divisions of the Nervous System The nervous system is divided into 2 main parts:The nervous system is divided into 2 main parts: –The Central Nervous System (CNS) –The Peripheral Nervous System (PNS) http://www.morphonix.com/software/education/science/brain/game/specimens/nervous_system.html

10. The Central Nervous System (CNS) Consists of:Consists of: –The brain –The spinal cord

11. The Brain CerebrumCerebrum –Largest part of brain –All voluntary (you can control!) movements controlled here –Left side of brain deals with right side of body and vice versa CerebellumCerebellum –Second largest region –Coordination and balance “Bellum balance”“Bellum balance”

12. The Brain con’t….. Brain stemBrain stem –Connects brain to spinal cord –Consists of Medulla oblongata (heart rate, etc)Medulla oblongata (heart rate, etc) ThalamusThalamus –Receives messages from sense organs HypothalamusHypothalamus –Control center for hunger, fatigue, body temp

13. PARTS OF THE BRAIN

14. Parts of the Brain Fill-In

15. BRAIN CONTROL What parts of the brain control what???????

16. The Spinal Cord Communication link btw brain and rest of bodyCommunication link btw brain and rest of body REFLEXES are processed hereREFLEXES are processed here Can you name some common reflexes????????????Can you name some common reflexes????????????

17. Peripheral Nervous System (PNS) TWO FUNCTIONSTWO FUNCTIONS –TRANSFER IMPULSES FROM SENSE ORGANS  CNS –TRANSFER IMPULSES FROM CNS  MUSCLES OR GLANDS –Can you remember which neurons are involved?? SensorySensory MotorMotor

18. Peripheral Nervous System (PNS) TWO PARTSTWO PARTS –SOMATIC NS VOLUNTARY MOVEMENTSVOLUNTARY MOVEMENTS –AUTONOMIC NS INVOLUNTARY ACTIONSINVOLUNTARY ACTIONS –HEARTBEAT –GLAND STIMULATION