Scientists are studying a drug to see how effective it is at reducing the production of usable energy in cells. What should the scientists measure to determine whether the drug is effective?
A. the amount of ATP in cells
B. the amount of RNA in cells
C. the number of nerve signals produced by cells
D. the number of new cells produced by old cells
A. the amount of ATP in cells
ATP (adenosine triphosphate) is the molecule that carries energy within cells, so measuring the amount of ATP in cells would directly reflect the ability of the drug to reduce the production of usable energy.