Which of the following mutations would be most likely to impair production of a normally functioning protein?
a. insertion of three bases in a row
b. deletion of a single base
c. a point mutation within an intron
d. a mutation that changes a c to a g

B

Explanation:

The deletion of a single base is the mutation that would most likely impair the production of a protein, because each aminoacid is coded by a triplet of three base pairs. So when one of the bases is deleted, the whole series of triplets is altered so the whole series of aminoacids in the protein would now be different.

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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