The current knowledge concerning cells is the result of the investigations and observations of many scientists. the work of these scientists forms a well-accepted body of knowledge about cells. this body of knowledge is an example of a:
a) hypothesis
b) controlled experiment
c) theory
d) research plan

This body of knowledge is an example of a theory.

Explanation:

The scientific theory is a conceptual framework used to explain facts or phenomena and to make predictions.

The theory is fundamental to science because it allows scientists to organize and understand observations.

The construction of a theory begins with a hypothesis. The scientist believes that a certain phenomenon occurs in a certain way and so he/she performs observations under the scientific method to prove that his/her hypothesis is valid or not valid. The systematization of the observations as well as of the empirical data collected might derive in a scientific theory that can explain the analyzed phenomenon.

A scientific theory is a knowledge that was contrasted in several ways.

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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the animal that would be cutest if scaled down to the size of a cat? elephant