What statement best describes an independent variable? .
a. the factor that's changed by the experimenter and impacts the dependent variable.
b. the factor that's not changed by the experimenter and is impacted by the dependent variable.
c. the factor that does not change, but impacts the constant in an experiment.
d. the factor that's changed by the experimenter and impacts the constant in an experiment

his research revealed two genetically different groups of prokaryotes, which justified splitting kingdom monera into two kingdoms. the genetic and cellular differences were so great, that these two kingdoms were eventually placed into different domains in the current three-domain system.

the generally accepted parts of modern cell theory include: all known living things are made up of one or more cells. all living cells arise from pre-existing cells by division. the cell is the fundamental unit of structure and function in all living organisms.