Amoebas are heterotrophic organisms. This means they cannot produce their own food like autotrophs do (for example, plants that perform photosynthesis). Instead, amoebas obtain their nutrients by engulfing other organisms or organic matter from their environment.
To feed, amoebas use a process called phagocytosis, where they extend their cell membrane to form pseudopodia (false feet). These extensions surround and engulf their food, forming a food vacuole inside their cell. Once inside, the food is broken down by enzymes, allowing the amoeba to absorb the necessary nutrients.
In summary, amoebas are heterotrophic because they rely on external sources of organic material for nourishment rather than producing their own food.