Is amoeba proteus a heterotroph or an autotroph?

Answer 1

Amoeba is a heterotroph i.e they absorb their food directly from the external environment. Some are parasites. Amoeba eat algae, bacteria, plant cells and also protozoans.
Amoebas engulf their food. They are heterotrophs. They cannot make their own food.

Answer 2

Heterotrophs are organisms which cannot make their own organic substances (eg carbohydrates, proteins etc) and so have to obtain them ready-made by eating food. Autotrophsare organisms which can make their own organic substances from inorganic materials eg water and carbon dioxide. Plants are autotrophs. Amoeba proteus is a free-living heterotroph, which feeds on other microscopic organisms such as ciliates and algae. These are ingested (taken into the cell) by pseudopodia, or "false feet". These are extensions of the cytoplasm which surround the prey and trap it in a tiny drop of water, forming a food vacuole. Enzymes are then added to the vaculoe to digest the food. Useful substances are absorbed into the cell while indigestible materials are passed out. For a very interesting article about Amoeba, with excellent photographs, see: http://www.microscopy-uk.org.uk/mag/artsep01/amoeba.html

Answer 3

An amoeba is heterotrophic.