Unilateral deafness (deafness in one ear) is caused by an autosomal dominant allele (D). The ability to curl the tongue is also caused by an autosomal dominant allele (T). A woman, heterozygous for both traits marries a man with normal hearing but who cannot curl his tongue. What is the probability of them having a child who can curl their tongue and is deaf in one ear?

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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