Predict the expected consequence(s) of applying a toxin that blocks voltage-gated Ca2+ channels in a neuron.

A. No resting membrane potential would be observed (i.e., measures at 0 mV).
B. Neuron conducts action potentials normally, but would not transmit these potentials across chemical synapses.
C. The neuron would become hyperpolarized.
D. A rapid increase in membrane potential at threshold voltage would not occur.
E. Membrane potential would increase rapidly to peak with an action potential, but would not decrease immediately afterward.


Answer: B

Biology & Microbiology

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