Answer:
The study of microbes in their natural habitat and their relationship with each other and their environment is termed as Microbial ecology. It mainly constitutes of Viruses, Eukaryotes ,Bacteria and Archaea as its living entities.
Being omnipresent in the biosphere they impact the other life-forms up to a significant extent.
They also help maintaining biogeochemical cycle by nitrogen fixation, sulfur metabolism and methane metabolism. Microbes also play a vital role of availing energy in the ecosystems where sunlight is scarce and hence photosynthesis is not good means of energy trapping, in such ecosystems the microbes actively engage in fundamental ecological processes including production, decomposition, and fixation inside the host organism.
Viruses are not considered alive, because they lack certain aspects that would be considered a living organism.
The phospholipid bilayer is a universal component of all cell membranes. Each phospholipid molecule has a hydrophobic(water repelling) and a hydrophilic( attracted to water) end. This allows the phospholipids to arrange themselves in a way that makes a cell membrane not able to dissolve in water. The bilayer is also semi-permeable which allows only certain molecules to enter the cell.
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