If a piece if DNA breaks off from a chromosone and attaches itself to a nonhomologous chromosome at another location, what type of change has occured?

Mutation (Translocation)

Explanation:

Many at times, changes occur in the genetic material. These changes alter the sequence of the genes in the genome. These changes are called MUTATION. Mutation is any change, whether small or large, in the genetic sequence of a DNA. Mutation is of different types depending on how and it occurs.

When the change occurs in a manner in which chromosomal segment breaks off and is reattached to another different chromosome, it is called TRANSLOCATION MUTATION.

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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i am positive it is c. condensing but i may be wrong