METABOLY is the active squirming motion which is characteristic of many euglenids. It is made possible by the sliding of strips within the pellicle.
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All euglenids, such as Eutreptia on the left have a cell surface that is ridged. When the cytoplasm is digested away, it is possible to see that the ridges are created by interlocking strips of cytoskeletal material. |
The use of motility proteins force adjacent strips to move relative to each other, and the resulting tensions lead to bending and flexing of the cell.