Eva is performing an experiment to determine which type of disinfectant kills the most bacteria. she has six plates of the same kind and amount of bacteria. she adds one of five different kinds of disinfectant to each plate and leaves one plate without any disinfectant as a control. what role does the independent variable play in this experiment?

Gregor mendel is best known for his work with pea plants and for uncover many of the mysteries of genetics. one of his major findings stated that there were specific, physical units of inheritance that are transmitted during reproduction. what is the the name given to these units of inheritance which can be found on chromosomes? a) centromeres b) cytoplasm c) genes d) nucleotides

What do isotopes of uranium have the same number of? what do they have a different number of? a) same number of protons; different number of electrons b) same number of protons; different number of neutrons c) same number of electrons; different number of protons d) same number of neutrons; different number of protons

14. which of the following codons code for threonine? a. ucg b. ugu c. cga d. aca