Observation Examples of Living Organisms

This image shows Bacillus cereus, which is a kind of bacteria that causes food poisoning. The oval (diameter: approx. 2.3 mm; minor axis: approx. 1.7 mm) spores and the trophozoite cells of length approx. 7 mm can be seen. In contrast to the smooth surfaces of the spores, many bumps can be observed on the surfaces of the trophozoite cells. This difference probably reflects a difference in the resistance of the two types of cell to air-drying.