Define recombination and why does
it lead to mutations?

Recombination is a process by which pieces of DNA are broken and recombined to produce new combinations of alleles. In eukaryotic cells, which are cells with a nucleus and organelles, recombination typically occurs during meiosis. Meiosis is a form of cell division that produces gametes, or egg and sperm cells.When translocation or recombination take place it results in a chromosome that differs from the original. This new chromosome has a mutation, or a change in genetic material. When a mutation occurs and DNA is exchanged between chromosomes, genetic variability is increased.

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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