One good use or consequence of bacteria?

I need this 4 my biology class, so i need this answer ASAP

One good use or consequence of bacteria?
One good use for bacteria is that it can supply your body with vitamin K. Your gut is colonized by bacteria that as a by-product of their metabolism produce vitamin K. Without this colonization you could have bleeding problems.
Reply:Cheese. Here's a government link:


http://www.newton.dep.anl.gov/askasci/bi...