This procedure was adapted from A Laboratory Manual for Microbiology , third edition, by John M. Larkin.
Microorganisms are ubiquitous in our environment.
Practically any area of the earth is inhabited by a micro ecosystem of life forms that may be uniquely adapted to that environment. All living cells share certain requirements for growth. C, H, O, N, P and S are the elements considered basic for cell growth. Molecular oxygen is essential for the growth of many but not all cells. All cells have a need for energy, which may be obtained by trapping sunlight and converting light energy to chemical energy, or by releasing the chemical energy contained in bonds within compounds.