Most of the fungi plants are saprophytic,so they use dead organic matter and converts it into inorganic compounds, which primary producers use in their metabolisms.
It is because that's a place where no one lives so they're safe.
Yes. You could do this by adding solvents to break down any cell walls, centrifuge to separate the DNA, if you haven't got much then upscale with PCR, gel electrophoresis could be used to detect the DNA, and Sanger sequencing to find the sequence.
Mammals do; I'm in my science class
