The principal structural elements of the cell wall in Coleochaete vegetative cells are cellulose microfibrils. Plasmodesmata are present in the cross walls between cells of the same filament.

Vegetative cells are uninucleate. Mitochondria are numerous and have flattened mitochondrial cristae. In general, organelle structure in vegetative cells is essentially identical to that observed in land plants, except that there is one plastid rather than many, and the plastid contains a pyrenoid (these latter two features are also found, however, in hornworts, a group of mosslike land plants). Cell division features a complex network of microtubules and membrane vesicles (the "phragmoplast"), again as found in all land plants.

Zoospores and male gametes bear minute polysaccharide scales on their cell surfaces. Their flagellar apparatuses consist of two basal bodies projecting laterally from the cell in a V-shaped configuration, and one or two flagellar roots. One of these roots forms a broad "spline" of more than 20 microtubules, and is associated with a multilayered structure proximally, features also found in all land plants that have swimming male gametes.

The sterile cells around the egg may have thickened and irregularly corrugated walls - as do "transfer cells" surrounding the egg in the archegonium of land plants.

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