axopodium

biology

Also known as: axopodia

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June 18, 2026

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An axopodium is a semipermanent pseudopodium found in certain protists, such as Radiolaria and Heliozoa. It consists of an axial rod surrounded by an ectoplasmic sheath. Pseudopodia, in general, are temporary projections of cytoplasm used for locomotion and feeding in protists, a process known as amoeboid movement. Axopodia are a distinct and more complex type of pseudopodium compared to others like lobopodia, filopodia, and reticulopodia. They are characterized by a central core of microtubules and an outer layer of flowing cytoplasm, which may contain organelles for capturing prey.12

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protist
Pseudopodia
Axopodia are much more complex than the other types of pseudopods. They are composed of an outer layer of flowing cytoplasm that surrounds a central core containing a bundle of microtubules, which are cross-linked in specific patterns. The outer cytoplasm may bear extrusible organelles used…
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Axopodia are much more complex than the other types of pseudopods. They are composed of an outer layer of flowing cytoplasm that surrounds a central core containing a bundle of microtubules, which are cross-linked in specific patterns. The outer cytoplasm may bear extrusible organelles used…
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protozoan
Amoeboid movement
…long, stiff protoplasmic extensions (axopodia) of the amoeboid (paraphyletic) heliozoans shorten and lengthen—the forward axopodia lengthen and become attached, while the posterior axopodia detach and retract—and the amoeba rolls slowly along. The foraminiferans move by extending slender pseudopodia (filapodia), which may be several millimetres long in some species. The…
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…long, stiff protoplasmic extensions (axopodia) of the amoeboid (paraphyletic) heliozoans shorten and lengthen—the forward axopodia lengthen and become attached, while the posterior axopodia detach and retract—and the amoeba rolls slowly along. The foraminiferans move by extending slender pseudopodia (filapodia), which may be several millimetres long in some species. The…
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pseudopodial locomotion
Structures
Axopodia are long and sticky pseudopodia with an internal rod made of microtubules; these are especially prominent in radiolarians and heliozoans.
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Axopodia are long and sticky pseudopodia with an internal rod made of microtubules; these are especially prominent in radiolarians and heliozoans.
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pseudopodium
…to form food traps; and axopodia, characteristic of the actinopods, are long and sticky (like reticulopodia) but radiate singly and have a stiff, internal rod composed of numerous microtubules. Lobopodia and filopodia are formed as the result of a pressure system; reticulopodia and axopodia depend on a two-way flow of…
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…to form food traps; and axopodia, characteristic of the actinopods, are long and sticky (like reticulopodia) but radiate singly and have a stiff, internal rod composed of numerous microtubules. Lobopodia and filopodia are formed as the result of a pressure system; reticulopodia and axopodia depend on a two-way flow of…
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