Bacteria

There is not much to talk about bacteria, but there is one thing that they are very good at, the same thing that viruses are masters of. They can replicate very quickly, making new bacteria that are either weaker, the same, or stronger. Weaker ones die, and stronger ones live to produce even stronger ones. This is the same with viruses, except that viruses do this faster. Bacterium are also self- sustaining, like your cells. Most crave heated places, like your own cells, and most are harmless. No wait, all are harmless. They just want an easy source of nutrients and resources, which is basically a multicellular being. Therefore, when they can get in, they will. Most are stopped by the front- line defenders, but some are not. The ones that get through can cause fatigue and sickness, and we will talk further in detail about how your body stops them. 

As I have said, all are harmless, if they can reach an agreement with your body, which you can see on your skin and in your intestines. How they do this is unclear, but they do. When they decide to make problems, though, they get taken care of.