Why are the filamentous body forms of slime molds (myxomycetes and acrasiomycetes), water molds (oomycetes) and the hyphae of fungi considered a case of convergent evolution?

Convergent evolution is the independent evolution of similar features in species of different lineages.

It creates analogous structures with similar form or function but these structures were not present in the last common ancestor of those groups.  

The filamentous body forms of slime molds, water molds and the hyphae of fungi  is considered a case of convergent evolution because the filaments shape is an adaptation for a nutritional mode as a decomposer.

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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