1. The Nervous System Andy Mankowski

2. Introduction Why is the nervous system important? http://www.human-nervous-system.com/wp-content/uploads/2009/07/human-nervous-system.png

3. Nervous System Structure Central Nervous System (CNS) Brain Spinal Cord Peripheral Nervous System (PNS) Sensory – carries impulses to CNS Motor – carries impulses from CNS Somatic Nervous System – voluntary Autonomic Nervous System - involuntary Nerve Cells – Neurons (~100 billion neurons in the human brain) Video

4. Neuron Structure http://kvhs.nbed.nb.ca/gallant/biology/neuron_structure.html

5. Dendrites – branched projections of a neuron that act to conduct the electrochemical stimulation received from other neural cells to the cell body or soma Soma – the cell body, contains the nucleus Axon – long, slender projection of a neuron that conducts electrical impulses away from the soma Myelin Sheath – electrically insulating layer around the axon, increases the speed of impulses Schwann Cell – part of PNS, help nerve development and regeneration, form myelin Node of Ranvier – Tiny gaps between Myelin Sheath, action potential speed Axon Terminals – The end branches of an axon, separated from neighboring neurons by a synapse Neuron Structure

6. Chemical Synapse http://schools-wikipedia.org/images/666/66667.png Video

7. Activity 1: Neuron Model Class activity Multiple students hold “dendrites” = ropes One student holds the “Soma” = container One student moves the “action potential” = plastic tube One student hold the axon terminal = container filled with neurotransmitters With a larger class there could be multiple neurons communicating

8. Activity 2: How fast can you process information? One person holds the yard stick up Second person is being tested at how fast they can respond to the yard stick falling The first person will release the yard stick and the second person will catch it. They will record where their hand grabs the yard stick. Using this formula: t = √2y/g, y = distance in inches, g = gravity constant: 385.8 in/sec^2 one can calculate the time it took to process the information and react to the object Variation with sound and dim lighting Record data

9. Activity 3: How sensitive is your skin? Put sand paper in order from most coarse to most fine (ideally more variety) Use corkboards and toothpicks to measure touch receptors on your skin. Measure the distance in which you can no longer feel two spots touching your skin. Measure different areas on your body. Fill out data sheet and graph and answer analysis questions.

10. References http://legacy.owensboro.kctcs.edu/gcaplan/anat/Notes/API% 20Notes%20K%20%20Neurons.htmhttp://legacy.owensboro.kctcs.edu/gcaplan/anat/Notes/API% 20Notes%20K%20%20Neurons.htm http://faculty.washington.edu/chudler/twopti.html http://faculty.washington.edu/chudler/chreflex.html http://faculty.washington.edu/chudler/chmodel.html http://en.wikipedia.org/wiki/Neuron http://en.wikipedia.org/wiki/Nervous_system Campbell, Neil A., Reece, Jane B., 2005. Biology. Pearson Education Inc., San Francisco, CA. pgs 1011-1044