Action Potentials
Glia & Tumors
The Synapse
400

To fire a signal, the membrane potential must hit this "magic number" (usually -55mV).

What is Threshold?

400

Most brain tumors are caused by mutations in these cells, not neurons.

What is Glia?

400

This ion rushes into the axon terminal to trigger the release of neurotransmitters.

What is Calcium?

800

This period prevents a signal from traveling backward up the axon.

What is the Refractory Period?

800

These glial cells produce the cerebrospinal fluid (CSF) that cushions the brain.

What are Ependymal cells?

800

When multiple signals arrive at a neuron at the exact same time to trigger a fire.

What is Spatial Summation?

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