Color blindness is a recessive, X-linked trait. A normal sighted man marries a female who is a carrier for colorblindness (but can see color fine herself.) What are the chances their female children will be colorblind?

75%
50%
25%
0%

-If they marry a normal man then 50% of their grandson or 25% of grandchildren will become color-blind. This can easily be understood by the following cross. Therefore for the case of carrier daughters, only 25% of their children will be colorblind. Which also means 50% of grandsons will be colorblind.

Explanation:

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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b.