This technique allows the ultrastructure cells and tissues to be imaged at nanometer resolution. TEM is the main technique to study biological systems nanometer resolution. Moreover, it gives really good opportunities to visualise an interesting target with surrounding structure, when unlabelled surroundings still remain hidden at fluorescence sample.
Knowledge of the cellular ultrastructure can contribute to an understanding of how cells and tissues function in both normal physiological and pathological state.
In order to be imaged, biological samples need a specific preparation. See protocol