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Osmotrophy is the uptake of dissolved organic compounds by osmosis for nutrition. Organisms that use osmotrophy are osmotrophs. Some mixotrophic microorganisms use osmotrophy to derive energy.[ citation needed ] The organisms that used osmotrophy are known to be an osmotrophs which are usually found in protists and fungi although exclusively osmotrophic feeding in contemporary ecosystems are restricted to microscopic bacteria thereby used the process of osmosis for the movement of food although some macroscopic animals like molluscs, sponges, corals, brachiopods and echinoderms used osmotrophic feeding as a supplemental food source.


Osmotrophy is a means of gathering nutrients in microscopic organisms that relies on cellular surface area to ensure that proper diffusion occurs throughout the cell. When organisms increase in size, the surface area per volume ratio drops and osmotrophy becomes insufficient to meet nutrient demands.

In stagnant waters photoautotrophs have a relative advantage over heterotrophic osmotrophs since the flux of photons as an energy source are not hindered at low temperatures, thus it depend on diffusion for mass acquisition through Brownian diffusion.

Fluid motion is important for osmotrophs because asymptotic reactions occurs in the absence of fluid motion. Movement brings cell that correspond to the highest gradients though diffusional core is safe on average concentrations.[ citation needed ]

Many types of basal eukaryotes, particularly Fungi and Protista, are osmotrophic. [1] [ citation needed ]

Example of these types of organisms are tapeworms and Trypanasoma.

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Heterotroph organism that ingests or absorbs organic carbon (rather than fix carbon from inorganic sources such as carbon dioxide) in order to be able to produce energy and synthesize compounds to maintain its life

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  1. "Osmotrophy - Biology-Online Dictionary". www.biology-online.org. Retrieved 2016-04-17.

Further reading

See also