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Nervous System (pg. 2). What effects did Morgan Spurlock’s lifestyle have on his experiment? If you were to re-run the test, what things would you do differently? Why?. Page #2 of notebook. Nervous System/ Communication. Topic. Vocab Term Definition
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Nervous System (pg. 2) • What effects did Morgan Spurlock’s lifestyle have on his experiment? • If you were to re-run the test, what things would you do differently? Why?
Page #2 of notebook Nervous System/Communication
Topic Vocab Term • Definition • Other important things about the topic (picture)
Nervous System • Nervous System: The body’s electrochemical communication network, consisting of all the nerve cells
CNS vs. PNS Central Nervous System: • Brain and Spinal Cord
Peripheral Nervous System: • Sensory and motor neurons that connect the CNS to the rest of the body • Anything not the brain/spinal cord
Types of Neurons Sensory Neurons: • Nerves that carry messages from the body’s tissue and sensory receptors inward towards the brain Motor Neurons: • Nerves that carry instructions from the CNS to the body’s muscles
Types of Neurons Sensory Motor
What is a neuron? Neuron = Nerve cell
The Neuron • Neuron = nerve cell • Job: To send information throughout the Nervous System
Dendrites Dendrites
Dendrites Dendrites: • Neuron’s bushy, branching extensions that receive messages from other neurons • Dendrites “Listen” • Mean ‘tree-like’
Cell Body Dendrites Cell Body Nucleus
Cell Body • …Body of the cell; where the Nucleus is • Information is collected and determined whether or not to be sent down the axon
Axon Axon terminal Dendrites Cell Body Axon Nucleus
Axon Axon • The neuron extension that passes messages through its branches to other neurons • Two parts: Axon and Axon Terminals • Axons ‘talks’ through process called synapse (we’ll discuss that later)
Recap 4 1 3 2
Myelin Sheath Axon terminal Dendrites Node of Ranvier Cell Body Axon Myelin Sheath Nucleus
Myelin Sheath Myelin Sheath • Fatty tissue layer encasing the axons of some neurons • Enables greater transmission speed as neural impulses hop from one s to the next • Node of Ranvier: Space in between the myelin sheaths
What happens when there is no Myelin Sheath? • Over time, covering gets damaged; causes neural transmission speed to decrease • Multiple sclerosis (MS), Parkinson's, and Alzheimer's
Page #3 of notebook Action Potential
Recap • Neurons send information across body • Dendrites listen/receive information • Axon talk/send information ACTION POTENTIAL IS THE PROCESS OF TELLING THE AXON TERMINALS TO SEND INFORMATION!!!!!!!!
Action Potential Action Potential: • Brief electrical charge that travels down the neuron’s axon
Action Potential Receive Information Send Information Action Potential!
AP: Step One 1. Resting Potential • Inside of cell has negative charge (~70mV) • Potassium (K) on inside; Sodium (Na) on outside • Cell is ready to jump into action!
AP: Step Two 2. Na+ Doors Open • Na+ channels open; Na+ ions from the outside enter the cell • Cell becomes more positive; will it reach the action threshold?!?
AP: Step Three 3. Depolarization • As Na+ is coming in, K+ doors open up; K+ ions from the inside leave the cell • Cell’s charge begins to level out (becoming more positive)
AP: Step Four 4. Action Potential Climax • Na+ channels close; no more Na+ ions can enter cell • Note: K+ ions are still leaving; what is that going to do to the electrical charge of the cell?
AP: Step Five 5. Repolarization • K+ ions continue to leave the cell • Cell is returning to a “resting level” stage
AP: Step Six 6. Hyperpolarization • K+ doors finally close; more K+ outside than Na+ inside • Result: Cell body is too negative; cell adjusts to reach resting potential once more.
AP: Step Seven Back to resting potential • The system is ready to go again!
Page #4 in notebook Synapse: Axons talking to Dendrites
Bell Ringer 11/6 Page #4 in notebook Does the process of action potential send messages to other neurons? If so, how? If not, what does it do then?
Recap • What are the parts of the neuron? What does each part do? • Action potential is getting messages from one end of neuron to the other
Recap: Action Potential • Like a wave: Electrical charge of cell goes up and down • That up and down of charge pushes the message down axon
Synapse • Now that the information is at the axon, it needs to be sent to another neuron Synapse: • The Junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron
Synapse Activity • Each row will have 1 dendrite, 1 axon terminal; everyone else is in the axon • Goal: to send down the most messages down the neuron • Dendrite receives message from Mr. D • Axon show the processes in the action potential • Axon terminal shoots message into bin
11/7/13: The Brain Page #5 of notebook Yesterday we showed how synapse worked and how sometimes synapse is blocked. Using that information, how does Tylenol work with neurons?
Look what I found! http://www.npr.org/blogs/health/2013/10/31/242158325/a-new-look-at-an-old-epilepsy-drug-yields-treatment-clue
11/7/13: Recap • Messages travel through the nervous system; this system is created by neurons • In the neuron: dendrites listen, axon terminals talk • Action Potential = message travels from dendrite to axon (SAME NEURON) • Synapse = messages travels from one neuron to the other (OTHER NEURON)