- Euglenoids usually reproduce asexually by
dividing longitudinally from apex to base and therefore appear
"two-headed" until cytokinesis is complete. The chromosomes
of euglenoids are permanently condensed and can often be seen
with light microscopy. The chromosomes separate and daughter
nuclei form as the parent nucleus constricts and divides. Before
cell division begins, the number of pellicle strips doubles so
that the pellicle of each daughter cell will be made up of half
of the new and half of the old strips.
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- Euglenoids sometimes form resting cysts if
environmental conditions become unfavorable due to low nutrients
levels or a low ratio of nitrogen to phosphorus. The cells swell
and become rounder, lose their flagella, and develop more paramylon
storage granules and a protective polysaccharide mucilaginous
wall to contain the cells until conditions improve. Reproductive
cysts continue to undergo cell division.
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- Under certain conditions, Euglena
enters a palmelloid stage where the cells become encased in mucilage
and divide repeatedly.
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