13) according to theories concerning the origin of life, the atom shown is a likely choice for the basic element of all livings things because it a) is small and unstable. b) is relatively stable and can form four covalent bonds. c) forms four ionic bonds with other elements and itself. d) is large and takes up enough space to fill the structure of a cell.

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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lesson summarykaryotypes a genome is the full set of all the genetic information that an organism carries in its dna. chromosomes arebundles of dna and protein found in the nucleus of a eukaryotic cell.

there's no big difference.

explanation:

the only little different between a rabbit and bunny is just that bunnies are much smaller than rabbits. bunnies are basically baby rabbits.

it is a. i hope this .