According to chargaff's rule, base pairing in dna should resemble which of the following? a = t; c = g a = c; t = g a = g; t = c a = u; c = g

The right answer is A = T; C = G.

Chargaff's rules indicate that the DNA of any cell or organism must have a ratio of 1 to 1 between purine bases and pyrimidine bases and, more specifically, that the amount of guanine is equal to the amount cytosine, and that the amount of adenine is equal to the amount of thymine. This trend is found in both strands of DNA.

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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