The drug was tested on a group of 50,000 elderly patients who had cancer. The tumors in most of the patients did not respond to the treatment.

The scientists concluded that the drug was not effective in fighting cancer.

What is the most important problem with the design of this investigation?

Cells destroy body cells infected by a virus or bacteria.

Define the apical impulse and describe its normal location, size, and duration. which abnormal conditions may affect the location of the apical impulse? explain the mechanism producing normal first and second heart sounds. describe the effect of respiration on the heart sounds. describe the characteristics of the first heart sound and its intensity at the apex of the heart and at the base. describe the characteristics of the second heart sound and its intensity at the apex of the heart and at the base.

Which term most precisely describes the cellular process of breaking down large molecules into smaller ones? a) catalysis b) metabolism c) anabolism d) dehydration e) catabolism