Where is the concentration of calcium ions ($ ext{Ca}^{2+}$) significantly higher than inside the presynaptic neuron?

Answer

Outside the neuron

The concentration of calcium ions is much higher outside the neuron, causing them to rush rapidly into the terminal down their electrochemical gradient when channels open.

Where is the concentration of calcium ions ($	ext{Ca}^{2+}$) significantly higher than inside the presynaptic neuron?

#Videos

2-Minute Neuroscience: Synaptic Transmission - YouTube

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