In fact, humans would not be able to live without the bacteria that inhabit the intestines. However, certain types of bacteria called coliform bacteria can signal the presence of possible drinking water contamination. A milliliter is one one-thousandth of a liter. A liter is a little more than a quart. A milliliter is about two drops from an eye dropper.
Pathogenic microorganisms are organisms capable of producing disease.
A Picocurie is a unit of radioactivity. A Curie is that quantity of any radioactive substance that undergoes 37 billion nuclear disintegrations per second. Thus a picocurie is that quantity of any radioactive substance that undergoes 0.037 nuclear disintegrations per second. Protozoa are microscopic animals that occur as single cells. Some protozoa can cause disease in humans.