Heterotroph

Heterotroph is an organism that cannot manufacture its own food and instead obtains its food and energy by taking in organic substances, usually plant or animal matter. All animals, fungi, and most bacteria and protists are heterotrophs.

Overview

In the food chain, heterotrophs are primary, secondary and tertiary consumers, but not producers. Living organisms that are heterotrophic include all animals and fungi, some bacteria and protists, and many parasitic plants.

Types of Heterotrophs

Heterotrophs can be further classified based on how they obtain energy. If the heterotroph uses chemical energy from the environment, then it is considered a chemoheterotroph. Most animals and fungi are considered chemoheterotrophs. On the other hand, if the organism uses light for energy, then it is considered a photoheterotroph.

Chemoheterotrophs

Chemoheterotrophs obtain their energy by consuming organic molecules, which they break down through cellular respiration. These organic molecules can include fats, carbohydrates, and proteins.

Photoheterotrophs

Photoheterotrophs, on the other hand, use light energy to produce ATP but they cannot use carbon dioxide as their carbon source. Instead, they use organic compounds from the environment to satisfy their carbon requirements.

Role in the Ecosystem

Heterotrophs play a crucial role in the ecosystem. They are the consumers in the food chain, feeding on autotrophs and other heterotrophs to drive the energy flow through the trophic levels. They also help in decomposing organic materials, returning nutrients back to the ecosystem.

See Also

• Autotroph
• Consumer (biology)
• Decomposer
• Food chain
• Trophic level

Heterotroph

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  Auto-and heterotrophs
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  AutoHeteroTrophs flowchart