The independent variable is the only factor that a scientist
varies for different groups in an experiment.
measures in an experiment.
keeps constant for each group in an experiment.
records throughout an experiment.

Cedure,© data: rmativetable 1: positive and negative results when imacromoleculeregative results when testing for the presence of macromoleculeschemical test | positive test result negative tcarbohydrates – simplesugarse negizitivecarbohydrates – 2: results for the presence of macromolecules in the evidence sample

Which group of chordates does  notpossess true backbones?                 a.  birds      b.  frogs and toads      c.  lampreys      d.  crocodilians

(amoeba sisters video recap: pedigrees and need