Dendrites: receivesSoma: cell body, houses

nucleusNucleus: processesAxon: carriesMyelin Sheath: insulates

& protects axonNodes of Ranvier: pinchesTerminal Buttons: sendsSynapse: space between

Number of extensions from the somaBipolarUnipolarMultipolar

Which direction they send messagesSensory/AfferentMotor/EfferentInterneurons: between

neurons in brain

Resting potential, polarizationAbsolute thresholdNA 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

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

Refractory period: after the terminal buttons release the synaptic vesicles across the synaptic gap, the neuron gets ready to fire again

PolarizationProcess starts again

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

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 itAntagonist: blocks it

Excitatory: makes the neuron more likely to fireAcetylcholing (ACh)NorepinephrineGlutamate

Inhibitory: makes the neuron less likely to fireDopamineSerotoninEndorphinsGABA

Include the following parts in your metaphor…DendritesSomaNucleusAxonMyelin sheathTerminal buttonsNeurotransmitters

Post OfficeDendrites: Blue mail

boxesSoma: Post officeNucleus: Filing stationAxon: Mail carrierMyelin sheath: TruckTerminal buttons:

individual mail boxesNeurotransmitters:

letters