Gated ion channels: a. transmit electrical signals.
b. only allow passage of Na+ and K.
c. open or close based solely on changes in membrane potentials.
d. allow passage of neurotoxins into cells.

explanation:

on disadvantage of hydroelectric power is the cost. another disadvantage of using hydroelectric power is finding a water source powerful enough to harvest hydroelectric power.

the farther away the object is from the central star (the sun) it's gravitainal pull on the object is weaker when it is farther

explanation:

answer; incomplete dominance;

answercells,tissues,organs,organ,system-organism;

levels of biological organization; organism,population,community,ecosystem,biome,biosphere,

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