1. Nervous System Group 1 Abbey Mui, Charlotte Fletcher, Jake Morrissey, Elise DeFazio

2. Motor Neuron Structure Cell Body/Soma ●Bulbous end of the motor neuron containing the cell nucleus (1)

3. Motor Neuron Structure Dendrites ●Impulses received from other cells at synapses are transmitted to the cell body. ●Electrochemical stimulation can then be passed through the motor neuron (1)

4. Motor Neuron Structure Axons ●Elongated fiber of a nerve cell ●Larger size=faster transmitting time ●Most neurons have only one axon ●May or may not have myelin sheath (2)

5. Motor Neutron Structure Myelin Sheath ●Electrically insulating material, insulates from electrically charged atoms and molecules ●Impulse is moved by saltatory conduction, which increases conduction velocity (2) ●saltatory conduction- allows impulses to “skip” along the axon, like the way in which a thrown stone can skip along the surface of water.

6. Motor Neuron Structure Axon terminal ●Branch-like structure ●Where electrical impulse leaves (2)

7. Two Major Types of Ions ● Potassium and Sodium are the major types ions that cross the plasma membrane. ● K + (potassium) ● Na + (sodium) (1)

8. Movement of the Ions ● For every 3 sodium ions actively transported out of the neuron, the sodium–potassium pumps actively transport 2 potassium ions in. ●This is happening when the neuron is at rest to create a large concentration gradient (3)

9. Proteins in the Membrane of a Neuron

10. Action Potential ● In neurons, they play a central role in cell-to-cell communication. In other types of cells, their main function is to activate intracellular processes. In muscle cells, for example, an action potential is the first step in the chain of events leading to contraction. (3) ● When a strong enough signal or stimulus occurs, Na + ions flood in due to the large concentration gradient allowing for the electrical signal to continue to travel.

11. Action Potential

12. Works Cited 1)Starr, Cecie, and Ralph Taggart. Biology the Unity and Diversity of Life. N.p.: Thomas Learning, 2001. Print. 2)Lodish, H. "Overview of Neuron Structure and Function." NCBI. W.H. Freeman Company, 2000. Web. 17 Nov. 2014. <http://www.ncbi.nlm.nih.gov/books/ NBK21535/>. 3)The Future of Humans. West One Services, n.d. Web. 17 Nov. 2014. <http://tle.westone.wa.gov.au/content/file/ 969144ed-0d3b-fa04-2e88-8b23de2a630c/1/human_bio_science_3b.zip/content/ 002_nervous_control/page_03.htm>.