phagotrophy

biology

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July 23, 2026

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Phagotrophy is a method of nutrition where an organism engulfs solid particles of food. This process is essential for many single-celled organisms, such as amoebas, which use it as their primary way of feeding. In more complex animals, specialized cells called phagocytes, like white blood cells, perform phagocytosis. These cells play a crucial role in the immune system by engulfing and destroying foreign substances such as bacteria and dead cells.1

The process involves the phagocyte flowing around the particle until it is completely enclosed within a food vacuole, called a phagosome. Inside the phagosome, the particle is digested by enzymes. Phagocytosis can be aided by opsonins, which are proteins that coat particles, making them easier for phagocytes to adhere to and engulf. This mechanism is vital for both feeding in simpler organisms and defense against pathogens in more complex ones.12

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digestion
Ingestion
…a method of feeding called phagotrophic nutrition. Many protozoans also are osmotrophic to a lesser degree. Some organisms, such as amoebas, have pseudopodia (“false feet”) that flow around the food particle until it is completely enclosed in a membrane-bounded chamber called a food vacuole; this process is called phagocytosis.
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…a method of feeding called phagotrophic nutrition. Many protozoans also are osmotrophic to a lesser degree. Some organisms, such as amoebas, have pseudopodia (“false feet”) that flow around the food particle until it is completely enclosed in a membrane-bounded chamber called a food vacuole; this process is called phagocytosis.
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protist
Respiration and nutrition
…of at least two types: phagotrophy, which is essentially the engulfment of particulate food, and osmotrophy, the taking in of dissolved nutrients from the medium, often by the method of pinocytosis. Phagotrophic heterotrophy is seen in many ciliates that seem to require live prey as organic sources of energy, carbon,…
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…of at least two types: phagotrophy, which is essentially the engulfment of particulate food, and osmotrophy, the taking in of dissolved nutrients from the medium, often by the method of pinocytosis. Phagotrophic heterotrophy is seen in many ciliates that seem to require live prey as organic sources of energy, carbon,…
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marine ecosystem
The pelagic food chain
Moreover, heterotrophic protists (phagotrophic protists) are now viewed as the dominant controllers of both bacteria and primary production in the sea. Current models of pelagic marine food chains picture complex interactions within a microbial food web. Larger metazoans are supported by the production of autotrophic and heterotrophic cells.
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Moreover, heterotrophic protists (phagotrophic protists) are now viewed as the dominant controllers of both bacteria and primary production in the sea. Current models of pelagic marine food chains picture complex interactions within a microbial food web. Larger metazoans are supported by the production of autotrophic and heterotrophic cells.
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