What ecolutionary reason would cause an organism to live long?

Which of the following are false concerning microbes? a. microbes generate oxygen through photosynthesis.b. the primary role of microbes on the planet involves causing disease in animals and humans.c. microbes produce vitamins in the intestines.d. microbes play a role in breaking down waste and decomposing dead organisms.

In what for do plants utilize nitrogen? why do they need nitrogen?

How are mutations continually being generated in a population (what are some of the causes of mutatuions? ) explain