Magnified 3000X, this 2002 scanning electron microscope (SEM) image revealed part of the ultrastructure exhibited by a number of Hartmannella vermiformis amoeba cysts. The amoeba assumes the cystic stage of its life cycle under harsh conditions such as drought, or when there is an accumulation of toxins in its environment, which can reduce its metabolic needs. Under these circumstances, the protozoan produces a protective coat and goes dormant to wait for better conditions. There is another major life cycle stage that this organism goes through known as the trophozoite stage which is its vegetative phase. At this point, the creature spends time feeding, moving, and reproducing. This free-living protozoan moves in response to chemical cues in its environment by extending pseudopodia or false feet. CDC/Dr Rodney Donlan 2002