Answer:
Gated ion-channels
Explanation:
These ion channels are protein molecules that act as a passageway which span across the cell membrane allowing the movement of ions from one side of the membrane to the other. They possess the ability to open and close in response to either chemical or mechanical signals.They possess a fluidic pore, which becomes available to ions after a conformational change in the protein structure has been activated causing the ion channel to open. Based on the stimulus to which they respond, ion channels are divided into three groups: voltage-gated, ligand-gated and mechano-sensitive ion channels. Channels responding to electrical (voltage-dependent ion channels), mechanical, or chemical (ligand-gated ion channels) stimuli open and allow rapid ion movement into or out of the cell, and this movement creates an electrical signals.
<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
Marie and Pierre Curie successfully isolate radioactive radium salts from the mineral pitchblende in their laboratory
They transport amino acids