<h2>Sodium channels </h2>
Explanation:
Depolarization is a result of sodium channels opening as a result of chemical or pressure-based stimuli
- Depolarization starts when a threshold stimulus applied on a neuron via Na+ mechanically operated channels that trigger action potential
- Action potential is an efficient signaling process by which distantly located cells communicate to each other
- Depolarization of membrane potential is due to influx of Na+ via voltage gated Na+ channels
- Fast opening of voltage gated Na+ channel shifts membrane potential from -70mV to + 50mV at which voltage gated Na+ channels become inactive thus influx of Na+ abruptly stops
Among the northern Andean countries strongly involved in the illegal coca and drug trade, Columbia is now the predominant coca producer, so the answer would be option A.
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