Gregor mendel called the generation created by crossbreeding the parental generation the
(a) second parental generation.
(b) cross filial generation.
(c) second filial generation
(d) first filial generation.

First filial generation.

Explanation:

Mendel is known as the father of genetics. He formulated the law of segregation and law of independent assortment by working on the pea plant.

The Mendel first crossed the pure breed line parents and obtained the first filial generation. The F1 generation is obtained by the cross breeding of the parental generation.

Thus, the correct answer is option (D).

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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