Progressive development of geniculations ('knee bends') associated with lateral conjugation: this may be Mougeotia geniculata. The cell diameter is 32µm.

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Sometimes the side braches reach several cells in length
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Cell contents change their appearance: the chloroplast contracts and becomes more dense, contracting away from the other organelles

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18

A general view of the filaments:

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The organelle which appears to have subunits is a pyrenoid (starch storage body)
3

1
The bulge in the cell wall grows until it develops into a tube: when the end opens the spore escapes:
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25

13  14

15  20

21  28

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24  26

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