2. Dendrites: receives Soma: cell body, houses nucleus Nucleus: processes Axon: carries Myelin Sheath: insulates & protects axon Nodes of Ranvier: pinches Terminal Buttons: sends Synapse: space between

4. Number of extensions from the soma Bipolar Unipolar Multipolar Which direction they send messages Sensory/Afferent Motor/Efferent Interneurons: between neurons in brain

5. Resting potential, polarization Absolute threshold NA channels open, negatively charged NA begins to enter neuron K channels open, K begins to leave the neuron Enough stimulation causes the cell to shift from positive to negative The sudden shift is called action potential

6. Depolarization: the shift in the charge, making it negative Once action potential passes through the axon, sodium gates close All-or-none principal: a neuron can’t accept more messages until the terminal buttons have sent it

7. Refractory period: after the terminal buttons release the synaptic vesicles across the synaptic gap, the neuron gets ready to fire again Polarization Process starts again

9. Neurotransmitters are released from vesicles in the terminal buttons Cross the synapse and taken up by receptors in new dendrites Neurotransmitters not taken in by dendrites are reabsorbed by sending neuron: reuptake

11. Each neurotransmitter has a specific receptor site that acts as a key When locked, neurotransmitters either have an excitatory or inhibitory effect Drugs: Agonist: acts like it Antagonist: blocks it

12. Excitatory: makes the neuron more likely to fire Acetylcholing (ACh) Norepinephrine Glutamate Inhibitory: makes the neuron less likely to fire Dopamine Serotonin Endorphins GABA

13. Include the following parts in your metaphor… Dendrites Soma Nucleus Axon Myelin sheath Terminal buttons Neurotransmitters Post Office Dendrites: Blue mail boxes Soma: Post office Nucleus: Filing station Axon: Mail carrier Myelin sheath: Truck Terminal buttons: individual mail boxes Neurotransmitters: letters