<span>plastics are poor insulators because the electrons in the atom are tightly bound and unable to move between other atoms. </span>
Answer: 1. B. Endothermic
2. B. Decreases
3. A. Increases
Explanation:
When the temperature of a substance decreases to the substance's freezing point, the substance will begin to change from
a liquid to a solid.
The Ca2+ release-activated Ca2+ (CRAC) channel is the most well-documented of the store-operated ion channels that are widely expressed and are involved in many important biological processes. However, the regulation of the CRAC channel by intracellular or extracellular messengers as well as its molecular identity is largely unknown. Specifically, in the absence of extracellular divalent cations, it becomes permeable to monovalent cations with a larger conductance, however, this monovalent cation current inactivates rapidly by an unknown mechanism. Here we found that Ca2+ dissociation from a site on the extracellular side of the CRAC channel is responsible for the inactivation of its Na+ current, and Ca2+ occupancy of this site otherwise potentiates its Ca2+ as well as Na+ currents. This Ca2+-dependent potentiation is required for the normal functioning of CRAC channels.
Current is a flow of electrical charge carriers, usually electrons or electron-deficient atoms.
Learn more about current here:
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