Amoeboid locomotion is the usual mode of movement in (adherent) eukaryotic cells, e.g. amoebas, slime moulds, leukocytes and sarcomas etc etc. It also features in biological processes such as embryonic development, wound healing, and cancer metastasis.
It's accomplished by protrusion of cytoplasm of the cell involving the formation of pseudopodia ('false-feet'), and is known to involve controlled transitions of parts of the protrusions between 'sol' and 'gel' states.
Although the movement has been observed and extensively studied since it was possible to see moving amoebas under the microscope, the exact mechanisms involved are still unknown.
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