decomposer

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Diagram of a terrestrial food chain showing plants as primary producers, eaten by herbivorous mammals and insects, which are consumed by small and large predators, with decomposers like fungi, bacteria, and earthworms recycling organic matter.

Discern between self-sustaining autotrophs and consumer heterotrophs and find their places in the food chain

The role of fungi in forest decomposition

decomposer

biology

Also known as: decay organism, transformer

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Last updated

June 17, 2026

Quick Summary

Diagram of a terrestrial food chain showing plants as primary producers, eaten by herbivorous mammals and insects, which are consumed by small and large predators, with decomposers like fungi, bacteria, and earthworms recycling organic matter. — terrestrial food chain The terrestrial food chain featuring producers, consumers, and decomposers.

In biology, decomposers, also known as saprotrophs, are organisms that feed on nonliving organic matter, such as dead plants and animals. They play a crucial role in decomposition and nutrient cycling within ecosystems.1

Key decomposers include:
* Fungi: Highly efficient at breaking down complex plant matter like cellulose, returning nutrients to the ecosystem.1
* Bacteria: Effective at decomposing animal tissues and are also involved in nutrient cycles like nitrogen.12
* Water molds: Important decomposers in freshwater environments.1

These organisms break down organic material into simpler molecules through absorptive nutrition, using enzymes to digest their food externally before absorbing it. This process is vital for recycling essential elements like carbon and nitrogen, making them available for producers like plants.123

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carbon cycle
…as CO₂ by decay, or decomposer, organisms (chiefly bacteria and fungi) in a series of microbial transformations.
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…as CO₂ by decay, or decomposer, organisms (chiefly bacteria and fungi) in a series of microbial transformations.
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ecosystem
Trophic levels
…chains is made up of decomposers, those heterotrophs (such as scavenging birds and mammals, insects, fungi, and bacteria) that break down dead organisms and organic wastes into smaller and smaller components, which can later be used by producers as nutrients. A food chain in which the primary consumer feeds on…
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…chains is made up of decomposers, those heterotrophs (such as scavenging birds and mammals, insects, fungi, and bacteria) that break down dead organisms and organic wastes into smaller and smaller components, which can later be used by producers as nutrients. A food chain in which the primary consumer feeds on…
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inland water ecosystem
Population and community development and structure
…and macrophytes), consumers (animals), and decomposers (bacteria, fungi, small invertebrates)—that are interconnected by a complex web of links. Energy passes through these trophic levels primarily along the grazer and detrital chains and is progressively degraded to heat through metabolic activities. Meanwhile, the essential elements follow pathways that cycle between these…
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…and macrophytes), consumers (animals), and decomposers (bacteria, fungi, small invertebrates)—that are interconnected by a complex web of links. Energy passes through these trophic levels primarily along the grazer and detrital chains and is progressively degraded to heat through metabolic activities. Meanwhile, the essential elements follow pathways that cycle between these…
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trophic level
A separate trophic level, the decomposers or transformers, consists of organisms such as bacteria and fungi that break down dead organisms and waste materials into nutrients usable by the producers.
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A separate trophic level, the decomposers or transformers, consists of organisms such as bacteria and fungi that break down dead organisms and waste materials into nutrients usable by the producers.
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