Which is a correct statement about mutation? A: Mutation decrease variety in the population.
B: Mutation increase variety in a population.
C: Mutation ensure alleles never change.
D: Mutation are always bad.

B: Mutation increase variety in a population.

Explanation:Mutations are changes to an organism's DNA and are an important driver of diversity in populations. Species evolve because of the accumulation of mutations that occur over time. This mutation has introduce a new allele into the population that increases genetic variation and may be passed on to the next generation.

the answer is b: 1.4 km/hr

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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