Spirogyra

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Spirogyra
Spirogyra in conjugation

Spirogyra in conjugation

Systematics
without rank: Chloroplastida
without rank: Charophyta
Class : Ornamental algae (Zygnemophyceae)
Order : Yoke algae (Zygnematales)
Family : Zygnemataceae
Genre : Spirogyra
Scientific name
Spirogyra
link
Spirogyra in the light microscope
Spirogyra in the transmitted light microscope

Spirogyra ("screw algae") is a genus of green algae . It belongs to the Zygnemataceae family. The thread-like (trichal) Spirogyra often occurs in spring in calm waters as free-floating, thread-like, light green "cotton wool".

It is one of the yoke algae (multiplication by yoke formation) and has no flagellated stages. The chloroplast is coiled in a spiral (hence the name Spirogyra ).

A special ability of the Zygnemataceae is to be able to use the ionic hydrogen carbonate for photosynthesis when there is a shortage of dissolved carbon dioxide . In doing so, they give off hydroxide ions , so that the pH value of the water in the vicinity of the algae floss can rise to values ​​of up to 11.

Fossils of this genus are already known from the Carboniferous .

species

In Central Europe alone there are at least 120 species. For example:

  • Spirogyra mirabilis
  • Spirogyra setiformis
  • Spirogyra varians
  • Spirogyra fluviatilis
  • Spirogyra majuscula
  • Spirogyra juergensii
  • Spirogyra calospora
  • Spirogyra weberi

literature

  • Christian van den Hoek, Hans M. Jahns, David G. Mann: Algae . 3. Edition. Thieme, Stuttgart 1993, ISBN 3-13-551103-0

Individual evidence

  1. ^ Christian van der Hoek, Hans M. Jahns, David G. Mann: Algen . 3. Edition.
  2. ↑ Heinz Streble, Dieter Krauter: Life in the water drop . In: Kosmos Verlag (Hrsg.): Kosmos Naturführer . Kosmos Verlag, ISBN 978-3-440-15694-0 , pp. 186 .

Web links

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