上泽充通大学 Shanghai Jiao Tong University Limitations of microscopic count Dead cells and living cells are all counted Small cells are difficult to count Need phase contrast microscope Need high cell concentration,106 cells/ml (why?) Precision is difficult to achieve Motile cells must be immobilized before counting No.8 Shanghai Jiao Tong UniversityNo.8 Shanghai Jiao Tong University Limitations of microscopic count Dead cells and living cells are all counted Small cells are difficult to count Need phase contrast microscope Need high cell concentration, 106 cells/ml (why?) Precision is difficult to achieve Motile cells must be immobilized before counting