Amoebas use pseudopodia to move through their habitat and consume food. The term "pseudopodia" literally means “false feet.” In addition to helping amoebas move and consume food, some pseudopodia exhibit sensory functions.
To create a pseudopod, an amoeba extends a projection of its cytoplasm-filled body. If it intends to eat, it encircles the food particle with the pseudopod, forcing the particle into the amoeba’s body. If the amoeba seeks to move, it allows the extended pseudopod to serve as an anchor and allows cytoplasm from its body to flow into the pseudopod.
Amoebas of different species create pseudopodia of slightly different shapes. Scientists use these differences to help classify the species. However, it's important to note that amoebas aren't the only organisms that utilize an amoeboid body form; fungi, algae and animals also exhibit the body style. Likewise, some amoebas have different body forms and don't use pseudopodia.
Many amoebas are medically important species that can cause illness or death. However, countless other species inhabit the digestive systems of different animals and cause few or no ill effects. One example of a harmful amoeba is the brain-eating amoeba. Found in warm, fresh water, the organism gains entrance to humans when water enters the nasal passages.