is amoeba autotrophic or heterotrophic

Is amoeba autotrophic or heterotrophic? Every living being on this planet needs food in some way, and how that food is procured helps differentiate between heterotrophic and autotrophic organisms.

Now, amoeba, a single-celled eukaryotic organism, also needs food to survive.

But can it make its own? The answer will help determine if the amoeba is autotroph or heterotroph.

Turns out, the amoeba cannot make its own food and has to rely on external sources, which is why it is heterotrophic.

Fact: Amoeba is a single-celled organism that eats metazoa, bacteria, plant cells, protozoa, etc., and digest foods through vacuoles. 

Major Differences between Autotroph and Heterotroph

The primary distinction between autotrophs and heterotrophs is how they obtain their food.

Unlike heterotrophs, who must rely on the consumption of other creatures for their nutritional needs, autotrophs can generate their own food through chemosynthesis or photosynthesis.

differences between heterotroph and autotrophic

Algae, green plants and some bacteria are examples of autotrophs.

That is mainly because they can manufacture their own food using only the energy they receive from the sun or the chemicals in their surroundings.

These autotrophs work differently to produce food.

For instance:

  • Photosynthesis involves using chlorophyll to transform light energy into chemical energy.
  • Chemosynthesis involves the use of chemical processes to create organic chemicals from inorganic ones.

Conversely, heterotrophs get their nourishment and energy from external sources.

Heterotrophs include:

  • Fungus
  • Mammals
  • … and many microorganisms

They get the nutrition they need by digesting and absorbing the organic substances that other species produce.

Fact: Amoeba is capable of causing infections in hosts and the most common pathogenic amoebas are Acanthamoeba, Entamoeba histolytica, Naegleria folweri, and Balamuthia. 

The Ecological Roles of Heterotrophs and Autotrophs

The ecological roles of these organisms are also distinct. In most ecosystems, autotrophs are the first link in the food chain as the primary producers.

They serve as a source of nutrition and energy for heterotrophs and other species in the environment.

ecological roles of heterotrophs and autotrophs

In contrast, heterotrophs are essential to the ecosystem because of the function they play in ingesting and decomposing organic materials.

This in turn recycles nutrients and keeps things in check.

Keeping these differences in mind, it is interesting to know in which category you have to place an amoeba. But, first, let’s look into what an amoeba actually is. 

Is Amoeba Autotrophic or Heterotrophic?

When an organism cannot make its own food through photosynthesis but instead must rely on other sources, we call it heterotrophic.

And Amoebas fit this definition perfectly. Amoebae are examples of heterotrophs, which are organisms that get their food and energy from eating other species.

amoeba heterotrophic or autotrophic

Being members of the phylum Amoebozoa, amoebas are characterized by their lack of a nucleus.

They can be found in both freshwater and terrestrial settings, as well as in the ocean. 

In order to move and ingest food particles, amoebas employ projections called pseudopodia.

Understanding More about Amoebas

understanding more about amoebas

Amoebae are found in a wide variety of environments on every continent.

Some representative amoebas are shown below: 

A. Proteus Amoebae

This amoeba species is well-known and studied all over the world because of its frequent appearance in freshwater.

It is often used in research as a stand-in for other organisms. 

Histolytic Entamoeba

It is a parasitic kind of amoeba that lives in the human digestive system and can cause amoebic dysentery, a severe form of diarrhea with life-threatening complications. 

Dictyostelium Discoideum

It is a type of amoeba widely used as a research model.

In poor situations, it can develop multicellular structures, which it uses to hide itself in the earth and wait for suitable conditions. 


3d illustration of acanthamoeba

Among the amoeba, the genus Acanthamoeba is the most abundant in both terrestrial and aquatic environments.

Human infections can be caused by some species, especially those with compromised immune systems.

Naegleria Fowleri

It is a type of amoeba that thrives in freshwater environments.

It is responsible for an extremely rare but potentially fatal brain and spinal cord infection known as primary amoebic meningoencephalitis


Species of the genus Arcella, which are amoebas with a chitinous shell, are common in freshwater environments.

It is widely employed by scientists interested in learning more about how cell membranes originate and operate.

Fact: Amoeba wants to have organic content in its surroundings to nourish and grow because the organic content is essential for the growth of the bacterial population.

How Does Amoeba Get Its Food?

Amoebae rely heavily on the process of phagocytosis as a means of obtaining nutrition.

Through this process, they swallow and digest tiny organisms like algae and bacteria.

acanthamoeba feeding process

The amoeba forms a food vacuole around the food particle using its pseudopodia. 

For the amoeba to get the nutrients and energy it needs, the meal must be broken down into smaller molecules by the enzymes.

Certain amoebas can also get their nutrition through a process called pinocytosis.

The amoeba’s ability to absorb tiny chemicals and fluids from its environment is referred to as pinocytosis. 

Pseudopodia enclose the fluid or molecule, which the amoeba then swallows into a vesicle that combines with lysosomes for digestion. 

What Does an Amoeba Eat?

what does an amoeba eat

Amoebas are able to adapt to many different habitats thanks to their ability to consume a wide array of creatures. 

In fact, the ability of amoebas to consume a wide variety of species, including algae, bacteria, and other microscopic protists, is one of their defining characteristics.

When classifying amoeba as a heterotrophic organism, it is important to know that amoebas lack the pigments and chloroplasts essential for photosynthesis.

Plants and certain protists use a process called photosynthesis to transform the energy and nutrients in sunlight into chemical compounds.

To put it simply, amoebas cannot make their own food since they do not have chloroplasts and the appropriate pigments for photosynthesis.

Instead, they have to get what they need from other organisms. And that makes them heterotrophic.

Fact: Amoebas are known for finding a way to survive in extreme conditions like in the vacuum of space or boiling hot water. 

The Role of Amoeba in the Ecosystem

role of amoeba in the ecosystem

It is safe to say that you cannot name an ecosystem without the contribution of amoebas.

They play an important part in nutrient cycling and decomposing organic matter as heterotrophs, which means they feed on species other than themselves. 

Role in the Soil Ecosystem

Amoebas play a crucial part in the health of the soil ecosystem.

Soil is home to a plethora of amoeba species, all of which subsist on microbial life.

Consuming these organisms aids in population control and ecosystem stability in the soil.

In addition, amoebas aid in the decomposition of organic materials in the soil, freeing up nutrients essential to plant growth. 

Role in Aquatic Ecosystems

role in aquatic ecosystems

Amoebas play a critical role in aquatic ecosystems as predators of a wide variety of microorganisms, including bacteria and algae.

Amoebae play an important role in preventing dangerous algal blooms and preserving water quality by controlling microbial populations in both freshwater and marine habitats.   

Role in Animal Digestion

It has been discovered that certain types of amoebas play an important role in animal digestion.

Amoebas like Entamoeba are commonly found in the digestive systems of humans and other animals. It is true that some Entamoeba species are damaging to their hosts.

But, there are many species that serve an advantageous purpose by aiding in the digestion of food and the release of helpful nutrients. 

Role in Medical Practice and Research

role in medical practice and research

Amoebas play a significant role in scientific study and medical practice.

Amoebas have served as model organisms in many fields of biology and medicine due to their distinct physiology and behavior.

Genetics, cell biology, and the causes of disease are only a few of the many fields that have benefited from their application.

Fact: It is fascinating to know that amoeba has a large genome, and it actually exceeds 290 base pairs in amoeba proteus. 


Is Amoeba autotrophic or heterotrophic? As amoebas cannot sustain themselves through sunlight, they are classified as heterotrophs and must obtain their nutrition from external sources.

Amoebas are able to adapt to different settings thanks to their ability to consume a wide variety of species.

They have found success and distribution throughout a wide range of ecosystems because of their engulfment and digestion of food particles via phagocytosis and pinocytosis.

And of course, they play a massive role in maintaining a balance in different ecosystems.