1. Nervous System

2. NERVOUS SYSTEM

3. Two Parts Central (CNS) Peripheral (PNS)

4. http://inside.salve.edu/walsh/cns_pns.jpg

5. Central Nervous System Brain Spinal Cord

6. The Brain Coordinates body activities Made up of approximately 100 billion neurons Divided into three major parts- –the cerebrum –the cerebellum –the brain stem (medulla)

8. Cerebrum Largest part of the brain Used for: –Thinking –Memory is stored –Movements are controlled –Impulses from the senses are interpreted.

10. Cerebellum Interprets stimuli from eyes, ears, muscles Controls voluntary muscle movements Maintains muscle tone Helps maintain balance

12. Medulla (Brain Stem) Connects brain to spinal cord Act as pathways connecting various parts of the brain with each other Controls involuntary actions –Breathing, digestion, heart beat

13. http://www.cbituk.org/GRAPHICS/brain.gif

14. The Spinal Cord Extension of the brain stem Bundles of neurons that carry impulses from all parts of the body to the brain and from the brain to all parts of your body

15. PERIPHERAL NERVOUS SYSTEM NERVES AND SENSES

16. Nerve Cells Neurons –Basic functioning units of the nervous system

17. http://ilearn.senecac.on.ca/aahs/health/IHP/ottawa/anatomy/neuron/map/neuron.html

18. http://35.9.122.184/images/40-AnimalStructureAndFunction/

19. Neurons Made up of a cell body and branches called dendrites and axons –Dendrites receive messages from other neurons and send them to the cell body –Axons carry messages away from the cell body

20. Any message carried by a neuron is called an impulse

21. Neurons A message carried by a neuron is called an impulse

23. Types of Neurons Sensory Motor Interneuron

24. Sensory Neurons Receive information Send impulses to the brain or spinal cord

25. Interneurons Send impulses from sensory neurons to motor neurons

26. Motor Neurons Conduct impulses from the brain or spinal cord to muscles or glands throughout your body

27. STIMULUS /RESPONSE

28. Synapse Small space across which an impulse moves from an axon to the dendrites or cell body of another neuron

29. Synapse As impulse reaches the end of an axon, axon releases a chemical Flows across the synapse Stimulates the impulse in the dendrite of the next neuron Impulse moves from neuron to neuron

30. http://www.med.harvard.edu/publications/On_The_Brain/Volume7/Number1/images/Neuron.jpg

31. http://mhln.com An impulse moves in only one direction across a synapse - from an axon to the dendrites or cell body of another neuron.

32. Peripheral Nervous System Connects body to brain & spinal cord 12 pairs of nerves from your brain (cranial nerves) 31 pairs from your spinal cord (spinal nerves) –Bundles of sensory and motor neurons held together by connective tissue

33. http://www.christopherreeve.org/Research/Research.cfm?ID=178&c=21

34. Peripheral Nervous System Two divisions –Somatic –Autonomic

35. http://abdellab.sunderland.ac.uk/lectures/Parmacology/Pics/anatomy/PNS.GIF

36. Somatic Nervous System Controls voluntary actions Made up of the cranial and spinal nerves that go from the central nervous system to your skeletal muscles

37. Autonomic Nervous System Controls involuntary actions-those not under conscious control-such as your heart rate, breathing, digestion, and glandular functions

38. http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/A/autonomic.gif

39. Reflexes Involuntary, automatic response to a stimulus Involves a simple nerve pathway called a reflex arc